Rozprawy doktorskie: „Turbine blade development”

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Jousselin, Olivier. "Development of blade tip timing techniques in turbo machinery". Thesis, University of Manchester, 2013. https://www.research.manchester.ac.uk/portal/en/theses/development-of-blade-tip-timing-techniques-in-turbo-machinery(da682144-7009-4cdc-8f52-ff7cd0cf1cf1).html.

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In the current gas turbine market, the traditional design-test-redesign loop is not a viable solution to deploy new products within short timeframes. Hence, to keep the amount of testing to an absolute minimum, theoretical simulation tools like Finite Element Modelling (FEM) have become a driving force in the design of blades to predict the dynamic behaviour of compressor and turbine assemblies in high-speed and unsteady flows. The predictions from these simulation tools need to be supported and validated by measurements. For the past five years, Rolls-Royce Blade Tip Timing (BTT) technology has been replacing rotating Strain Gauge systems to measure the vibration of compressor blades, reducing development times and costs of new aero engine programmes. The overall aim of the present thesis is to progress the BTT technology to be applied to aero engine turbine modules. To this end, the two main objectives of this project are: i. To improve the current validated Rolls-Royce BTT extraction techniques, through the development of novel algorithms for single/multiple asynchronous and responses. ii. To validate the improved extraction using simulated and real engine test data in order to bring the Turbine BTT technology to a Rolls-Royce Technology Readiness Level (TRL) of 4 (i.e. component and/or partial system validation in laboratory environment). The methodology adopted for the development of the novel algorithms is entirely based on matrix algebra and makes extensive use of singular value decomposition as a means for assessing the degree optimisation achieved through various novel manipulations of the input (probe) raw data. The principle contributions of this thesis are threefold: i. The development of new BTT matrix-based models for single/multiple non-integral and integral engine order responses that removed certain pre-processing assumptions required by the current method. ii. The development of BTT technology to operate under the constraint of having equally spaced probes, which is unavoidable in turbines and renders current BTT methods unusable for turbine applications. iii. The development of methods for extracting measurement uncertainty and signal to noise ratios that are based solely on the raw data, without reliance on simulated reference data. Following the verification and validation of the new processing algorithms against simulated data and against validated software with numerous examples of actual engine test data, a Rolls-Royce's Research & Technology (R&T) Critical Capability Acquisition and Capability Readiness (CCAR) review has accredited the novel techniques with a TRL of 4.

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Caraballo, Torrealba Edgar Jesus. "Modeling and Control Development for a Turbine Blade Testing Facility". Miami University / OhioLINK, 2019. http://rave.ohiolink.edu/etdc/view?acc_num=miami1574434292454319.

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Gorle, Jagan Mohan Rao. "Development of Circulation Controlled Blade Pitching Laws for Low-Velocity Darrieus Turbine". Thesis, Chasseneuil-du-Poitou, Ecole nationale supérieure de mécanique et d'aérotechnique, 2015. http://www.theses.fr/2015ESMA0021/document.

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L'étude développée dans cette thèse concerne le contrôle des performances et des lâchers tourbillonnaires au cours du cycle de rotation d'une hydrolienne à axe vertical de type Darrieus. L'élaboration d'une famille de lois de commande d'incidence de pales exploitant le principe de conservation de la circulation autour de profils en mouvement permet ici le contrôle du fonctionnement de l'hydrolienne ainsi que la maîtrise de son sillage tourbillonnaire afin de préserver l'environnement.L'écoulement 2D est simulé à l'aide du solveur incompressible de Star CCM+ afin de mettre en évidence l'effet de ce type de contrôle sur le rendement de la turbine pour différents points de fonctionnement. Ce modèle CFD a été utilisé pour améliorer l'analyse analytique en ce qui concerne l'extraction de l'énergie, la compréhension de l'écoulement autour de l'hydrolienne et le contrôle des tourbillons générés. La nouveauté de cette étude est l'élaboration de lois de commande de pales d'hydrolienne, basées sur des valeurs constantes et transitoires de la circulation, afin d'augmenter la puissance de la turbine tout en garantissant un contrôle efficace de la vorticité et ainsi prévenir de l'interaction entre les tourbillons et les pales. Une bonne comparaison est réalisée entre les résultats analytiques et numériques concernant les forces hydrodynamiques.En outre, une campagne d'essais a été menée afin d'acquérir des mesures quantitatives sur une hydrolienne de type Darrieus à pales fixes en terme de puissance, mais aussi des résultats qualitatifs pertinents comme la visualisation de l'écoulement autour des pales à différentes positions et pour différents points de fonctionnement. La mise en place complète d'un système PTV pour les mesures qualitatives et les étapes de traitement sont discutées et les divers paramètres obtenus à partir des études CFD sont validées en utilisant ces résultats PIV.L'étude expérimentale dans la présente recherche appo11e des informations détaillées sur les gradients de pression et de vitesse, les contours de vorticité et le critère Q qui ont servi à valider les visualisations obtenues numériquement
With key applications in marine renewable energy. the vertical axis water turbine can use current or tidal energy in an eco-friendly manner. However, it is difficult to reconcile optimal performance of hydrokinetic turbines and compliance wilh the aquatic environment as the main drawback of the turbines is the formation of non-linear flow structures caused by the unsteady movement of the blades. Eddies in the flow are advected and can interact with other blades, which leads to a reduction in power output. To limit this phenomenon, the turbines operate at high speeds, which are likely to reduce the shaft power. High speeds of rotational so forbid the passage of aquatic animais, and are the cause of a suction effect on the sediments.The objective of this thesis work is twofold. First, it aims to develop a blade pitch control to get the flow adjusted around the blade profile at any given flow configuration by incorporatin.g the profile's motion with respect to incident flow. Such a system intends to achieve the objective of operating at reduced speeds without vortical releases, which should allow achieving a high torque without causing damage to the environment.This thesis work is mainly carried out in three phases. ln the first phase, the irrotational flow over an arbitrary profile is formulated using conforma] mapping. Prospective potential flow application on the basis of Couchet theory (1976) is involved in the development of a control law that decides the blade pitching in a constant circulation framework. In the second phase, a numerical validation of the developed analytical work is presented using CFD to examine how the theoretical fomulation can be effectively applied to Darricus turbines. In the final phase, two prototypes are developed, one is classical Darrieus turbine with fixed blades, and other is the turbine with pitching blades for experimental measurements of performance as well as flow fields(by PIV) in order to validate the computational results

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Bai, Qian. "Development of a new process to reduce distortion in gas turbine blade forging". Thesis, Imperial College London, 2012. http://hdl.handle.net/10044/1/39131.

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The aim of this study is to develop a new process for high precision hot forging of Ti-6Al-4V gas turbine blade. In this new process, the work-piece is hot formed and then is clamped between the dies at high pressure for a certain time in order to decrease the distortion and increase the geometric accuracy. The feasibility study of the new process has been carried out in this thesis by using experiments and finite element (FE) modelling, providing a scientific understanding of the process. From the experimental and modelling work, it has been demonstrated that the new process proposed in this thesis is an effective way to reduce distortion in gas turbine blade forging. The study can be divided into three parts: interfacial heat transfer coefficient determination, material modelling, and Ti-6Al-4V hot forming. A closed form method to determine an interfacial heat transfer coefficient (IHTC) was developed, and a one-dimensional heat transfer model was proposed and validated. Heat transfer tests were performed to study the heat transfer between Ti-6Al-4V work-pieces with an initial temperature of 920°C and H13 dies with an initial temperature of 150°C. Temperature histories measured by thermocouples were obtained, and were used as an input for the closed form method. The effects of pressure, glaze thickness and surface roughness on IHTC between Ti-6Al-4V work-pieces and H13 steel dies were studied. Thermo-mechanical properties of Ti-6Al-4V were investigated for a temperature range of 820°C to 1120°C and a strain rate range of 0.1s-1 to 10.0s-1, using a Gleeble thermo-mechanical simulator. The flow softening mechanisms of Ti-6Al-4V during hot forming were studied. A set of unified elastic-viscoplastic constitutive equations for Ti-6Al-4V during hot forming were developed. Plastic strain for alpha and beta phase, isotropic hardening, normalised dislocation density, adiabatic heating, phase transformation, and globularisation of alpha phase were described in the set of constitutive equations. The developed material constitutive model was determined by fitting with experimental strain-stress curves from uniaxial compression tests, using an Evolutionary Programming (EP)-based optimisation method. Good agreements between the experimental and computed results were obtained: the error of predicted stress is under 10%. The general trend exhibited by softening mechanism of Ti-6Al-4V during hot forging is correctly fitted. Hot forming tests were conducted to study the effects on distortion during hot forming strips used as analogous to gas turbine blades. The effect of work-piece thickness and holding time on spring-back were investigated. The unified constitutive equations for Ti-6Al-4V and IHTCs were integrated with commercial FE software DEFORM/2D to simulate material flow and heat transfer in the hot forming process. The FE model was validated by experimental results. A good agreement was obtained between experimental and FE results for temperature history and thickness distribution. The stress state, temperature field and phase volume fraction were obtained from FE simulation. The FE model can be used to predict the extent of distortion in an appropriate FE software, and thus to optimise the new hot forging process for Ti-6Al-4V high precision gas turbine blade.

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Cigeroglu, Ender. "Development of microslip friction models and forced response prediction methods for frictionally constrained turbine blades". Columbus, Ohio : Ohio State University, 2007. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1181856489.

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Guo, Shengmin. "Heat transfer and aerodynamic studies of a nozzle guide vane and the development of new heat transfer gauges". Thesis, University of Oxford, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.389217.

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Jiang, Zhengyi. "Design, development and testing of an automated system for measuring wall thicknesses in turbine blades with cooling channels". Thesis, University of Manchester, 2016. https://www.research.manchester.ac.uk/portal/en/theses/design-development-and-testing-of-an-automated-system-for-measuring-wall-thicknesses-in-turbine-blades-with-cooling-channels(895ac153-e310-40e2-87c6-4e40654c9d5d).html.

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Cooling channels are designed in blades to protect the blades from damage at high temperature in a gas turbine. ELE Advanced Technology Ltd. is a UK company specialised in machining cooling channels in turbine blades using electro-chemical techniques. The wall thicknesses between these cooling channels and the surface of the turbine blade influences the performance of cooling channels and are required to be accurately machined and then inspected. At present, the company measures the wall thicknesses using a hand-held contact ultrasonic probe, which is time-consuming and not very accurate. In this project, an inspection machine has been designed and built for the purpose of automating the procedure of measuring wall thicknesses in turbine blades. The inspection machine measures wall thicknesses based on immersion ultrasonic testing technique and the actuator is a six-axis industrial robot controlled by a computer. Control algorithms have been developed to automate the entire measuring process. Acquired ultrasonic data is also automatically processed using Matlab scripts for wall thickness evaluation. However, prior to the ultrasonic measurement, the probe path has to be calculated. Matlab script has been developed to automatically calculate a probe path using a point cloud of the blade digitized on a CMM as an input. The calculation of the probe path, in general, involves triangulation, parameterisation and B-spline surface approximation. Normal 3D triangulation methods were tested; nevertheless, the results were unsatisfactory. Therefore, a triangulation algorithm is developed based on B-spline curve and 2D Delaunay triangulation. After the probe path is calculated, a localisation method, based on iterative closest point algorithm, is implemented to transform the probe path from CMM to the inspection machine. Several experiments were designed and conducted to study the capability of the ultrasonic probe. Experimental results confirmed the feasibility of using an immersion ultrasonic probe for measuring the wall thicknesses; however, the experiments revealed several limitations of immersion ultrasonic testing, such as the angle of incidence of ultrasonic waves must be maintained within an angular deviation of ±1° from the surface normal to achieve accurate test results. Wall thicknesses of three turbine blades from one batch were measured on the inspection machine. A CT scan image was used as reference to compare the measured wall thicknesses with results obtained using contact probes. The comparison showed the wall thicknesses measured on the inspection machine were much more accurate than using contact probes.

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Lynch, Stephen P. "The Effect of Endwall Contouring On Boundary Layer Development in a Turbine Blade Passage". Diss., Virginia Tech, 2011. http://hdl.handle.net/10919/77202.

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Increased efficiency and durability of gas turbine components is driven by demands for reduced fuel consumption and increased reliability in aircraft and power generation applications. The complex flow near the endwall of an axial gas turbine has been identified as a significant contributing factor to aerodynamic loss and increased part temperatures. Three-dimensional (non-axisymmetric) contouring of the endwall surface has been shown to reduce aerodynamic losses, but the effect of the contouring on endwall heat transfer is not well understood. This research focused on understanding the general flow physics of contouring and the sensitivity of the contouring to perturbations arising from leakage features present in an engine. Two scaled low-speed cascades were designed for spatially-resolved measurements of endwall heat transfer and film cooling. One cascade was intended for flat and contoured endwall studies without considering typical engine leakage features. The other cascade modeled the gaps present between a stator and rotor and between adjacent blades on a wheel, in addition to the non-axisymmetric endwall contouring. Comparisons between a flat and contoured endwall showed that the contour increased endwall heat transfer and increased turbulence in the forward portion of the passage due to displacement of the horseshoe vortex. However, the contour decreased heat transfer further into the passage, particularly in regions of high heat transfer, due to delayed development of the passage vortex and reduced boundary layer skew. Realistic leakage features such as the stator-rotor rim seal had a significant effect on the endwall heat transfer, although leakage flow from the rim seal only affected the horseshoe vortex. The contours studied were not effective at reducing the impact of secondary flows on endwall heat transfer and loss when realistic leakage features were also considered. The most significant factor in loss generation and high levels of endwall heat transfer was the presence of a platform gap between adjacent airfoils.
Ph. D.

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Sahay, Prateek. "Development of a Robotic Cell for Removal of Tabs from Jet Engine Turbine Blade". University of Cincinnati / OhioLINK, 2019. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1574417686354007.

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ALINEJAD, FARHAD. "Development of advanced criteria for blade root design and optimization". Doctoral thesis, Politecnico di Torino, 2018. http://hdl.handle.net/11583/2711560.

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In gas and steam turbine engines, blade root attachments are considered as critical components which require special attention for design. The traditional method of root design required high experienced engineers yet the strength of the material was not fully exploited in most cases. In the current thesis, different methodologies for automatic design and optimization of the blade root has been evaluated. Moreover, some methods for reducing the computational time have been proposed. First, a simplified analytical model of the fir-tree was developed in order to evaluate mean stress in different sections of the blade root and disc groove. Then, a more detailed two-dimensional shape of the attachment capable to be analyzed in finite element (FE) analysis was developed for dovetail and fir-tree. The model was developed to be general in a way to include all possible shapes of the attachment. Then the projection of the analytical model over the 2D model was performed to compare the results obtained from analytical and FE methods. This comparison is essential in the later use of analytical evaluation of the fir-tree as a reduction technique of searching domain optimization. Moreover, the possibility of predicting the contact normal stress of the blade and disc attachment by the use of a punch test was evaluated. A puncher composed of a flat surface and rounded edge was simulated equivalent to a sample case of a dovetail. The stress profile of the contact in analytical, 2d and 3d for puncher and dovetail was compared. As an optimizer Genetic Algorithm (GA) was described and different rules affecting this algorithm was introduced. In order to reduce the number of callbacks to high fidelity finite element (FE) method, the surrogate functions were evaluated and among them, the Kriging function was selected to be constructed for use in the current study. Its efficiency was evaluated within a numerical optimization of a single lob. In this study, the surrogate model is not used solely in finding the optimum of the attachment shape as it may provide low accuracy but in order to benefit its fast evaluation and diminish its low accuracy drawback, the Kriging function (KRG) was used within GA as a pre-evaluation of the candidate before performing FE analysis. Moreover, the feasible and non-feasible space in a multi-dimensional complex searching domain of the attachment geometry is explained and also the challenge of a multi-district domain is tackled with a new mutation operation. In order to rectify the non-continuous domain, an adaptive penalty method based on Latin Hypercube Sampling (LHS) was proposed which could successfully improve the optimization convergence. Furthermore, different topologies of the contact in a dovetail were assessed. Four different types of contact were modeled and optimized under the same loading and boundary conditions. The punch test was also assessed with different contact shapes. In addition, the state of stress for the dovetail in different rotational speed with different types of contact was assessed. In the results and discussion, an optimization of a dovetail with the analytical approach was performed and the optimum was compared with the one obtained by FE analysis. It was found that the analytical approach has the advantage of fast evaluation and if constraints are well defined the results are comparable to the FE solution. Then, a Kriging function was embedded within the GA optimization and the approach was evaluated in an optimization of a dovetail. The results revealed that the low computational cost of the surrogate model is an advantage and the low accuracy would be diminished in a collaboration of FE and surrogate models. Later, the capability of employing the analytical approach in a fir-tree optimization is assessed. As the fir-tree geometry has a higher complexity working domain in comparison to the dovetail, the results would be consistent for the dovetail also. Different methods are assessed and compared. In the first attempt, the analytical approach was adopted as a filter to select out the least probable fit candidates. This method could provide a 7\% improvement in convergence. In another attempt, the proposed adaptive penalty method was added to the optimization which successfully found the reasonable optimum with 47\% reduction in computational cost. Later, a combination of analytical and FE models was joined in a multi-objective multi-level optimization which provided 32\% improvement with less error comparing to the previous method. In the last evaluation of this type, the analytical approach was solely used in a multi-objective optimization in which the results were selected according to an FE evaluation of most fit candidates. This approach although provided 86\% improvement in computational time reduction but it depends highly on the case under investigation and provides low accuracy in the final solution. Furthermore, a robust optimum was found for both dovetail and fir-tree in a multi-objective optimization. In this trial, the proposed adaptive penalty method in addition to the surrogate model was also involved.

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Dyachuk, Eduard. "Aerodynamics of Vertical Axis Wind Turbines : Development of Simulation Tools and Experiments". Doctoral thesis, Uppsala universitet, Elektricitetslära, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-260573.

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This thesis combines measurements with the development of simulation tools for vertical axis wind turbines (VAWT). Numerical models of aerodynamic blade forces are developed and validated against experiments. The studies were made on VAWTs which were operated at open sites. Significant progress within the modeling of aerodynamics of VAWTs has been achieved by the development of new simulation tools and by conducting experimental studies. An existing dynamic stall model was investigated and further modified for the conditions of the VAWT operation. This model was coupled with a streamtube model and assessed against blade force measurements from a VAWT with curved blades, operated by Sandia National Laboratories. The comparison has shown that the accuracy of the streamtube model has been improved compared to its previous versions. The dynamic stall model was further modified by coupling it with a free vortex model. The new model has become less dependent on empirical constants and has shown an improved accuracy. Unique blade force measurements on a 12 kW VAWT were conducted. The turbine was operated north of Uppsala. Load cells were used to measure the forces on the turbine. A comprehensive analysis of the measurement accuracy has been performed and the major error sources have been identified. The measured aerodynamic normal force has been presented and analyzed for a wide range of operational conditions including dynamic stall, nominal operation and the region of high flow expansion. The improved vortex model has been validated against the data from the new measurements. The model agrees quite well with the experiments for the regions of nominal operation and high flow expansion. Although it does not reproduce all measurements in great detail, it is suggested that the presented vortex model can be used for preliminary estimations of blade forces due to its high computational speed and reasonable accuracy.

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Den, Heijer Francois Malan. "Development of an active pitch control system for wind turbines / F.M. den Heijer". Thesis, North-West University, 2008. http://hdl.handle.net/10394/2635.

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A wind turbine needs to be controlled to ensure its safe and optimal operation, especially during high wind speeds. The most common control objectives are to limit the power and rotational speed of the wind turbine by using pitch control. Aero Energy is a company based in Potchefstroom, South Africa, that has been developing and manufacturing wind turbine blades since 2000. Their most popular product is the AE1kW blades. The blades have a tendency to over-speed in high wind speeds and the cut-in wind speed must be improved. The objective of this study was to develop an active pitch control system for wind turbines. A prototype active pitch control system had to be developed for the AE1kW blades. The objectives of the control system are to protect the wind turbine from over-speeding and to improve start-up performance. An accurate model was firstly developed to predict a wind turbine’s performance with active pitch control. The active pitch control was implemented by means of a two-stage centrifugal governor. The governor uses negative or stalling pitch control. The first linear stage uses a soft spring to provide improved start-up performance. The second non-linear stage uses a hard spring to provide over-speed protection. The governor was manufactured and then tested with the AE1kW blades. The governor achieved both the control objectives of over-speed protection and improved start-up performance. The models were validated by the results. It was established that the two-stage centrifugal governor concept can be implemented on any wind turbine, provided the blades and tower are strong enough to handle the thrust forces associated with negative pitch control. It was recommended that an active pitch control system be developed that uses positive pitching for the over-speed protection, which will eliminate the large thrust forces. Keywords: pitch control, wind turbine, centrifugal governor, over-speed protection, cut-in wind speed, blade element-momentum theory, rotor, generator, stall, feathering.
Thesis (M.Ing. (Mechanical Engineering))--North-West University, Potchefstroom Campus, 2009.

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Ozturk, Burak. "Combined effects of Reynolds number, turbulence intensity and periodic unsteady wake flow conditions on boundary layer development and heat transfer of a low pressure turbine blade". [College Station, Tex. : Texas A&M University, 2006. http://hdl.handle.net/1969.1/ETD-TAMU-1150.

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Jami, Valentina. "Development of Computer Program for Wind Resource Assessment, Rotor Design and Rotor Performance". Wright State University / OhioLINK, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=wright1513703072278665.

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Peters, David W. "Tip leakage loss development in a linear turbine cascade". Thesis, This resource online, 1992. http://scholar.lib.vt.edu/theses/available/etd-09052009-040444/.

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Zaccaria, Michael A. "Development of a transonic turbine cascade facility". Thesis, Virginia Polytechnic Institute and State University, 1988. http://hdl.handle.net/10919/53201.

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This thesis describes the design and initial testing of a transonic turbine cascade facility. It is specifically concerned with the best way to obtain flow periodicity and repeatability through the cascade by the use of tailboards at the cascade exit. The problem of how to achieve flow periodicity and repeatability has not been completely resolved. An examination of the literature available on transonic turbine cascade testing indicates some researchers use no tailboards, some use a solid tailboard, and still others use a porous tailboard. In this thesis, the flow through the turbine cascade is tested for three different cascade exit configurations; no tailboard, a solid tailboard, and a porous tailboard. The cascade is also tested with the tailboard at different angles, to see what effect the angle of the tailboard has on the flow through the cascade. The data acquisition and flow visualization systems are discussed and some preliminary results are given.
Master of Science

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Joyce, Bryan Steven. "Development of an Electromagnetic Energy Harvester for Monitoring Wind Turbine Blades". Thesis, Virginia Tech, 2011. http://hdl.handle.net/10919/36354.

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Wind turbine blades experience tremendous stresses while in operation. Failure of a blade can damage other components or other wind turbines. This research focuses on developing an electromagnetic energy harvester for powering structural health monitoring (SHM) equipment inside a turbine blade. The harvester consists of a magnet inside a tube with coils outside the tube. The changing orientation of the blade causes the magnet to slide along the tube, inducing a voltage in the coils which in turn powers the SHM system. This thesis begins with a brief history of electromagnetic energy harvesting and energy harvesters in rotating environments. Next a model of the harvester is developed encompassing the motion of the magnet, the current in the electrical circuit, and the coupling between the mechanical and electrical domains. The nonlinear coupling factor is derived from Faradayâ s law of induction and from modeling the magnet as a magnetic dipole moment. Three experiments are performed to validate the model: a free fall test to verify the coupling factor expression, a rotating test to study the model with a load resistor circuit, and a capacitor charging test to examine the model with an energy storage circuit. The validated model is then examined under varying tube lengths and positions, varying coil sizes and positions, and variations in other parameters. Finally a sample harvester is presented that can power an SHM system inside a large scale wind turbine blade spinning up to 20 RPM and can produce up to 14.1 mW at 19 RPM.
Master of Science

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Meehan, Edward Charles. "Development of embedded sensors for structural health monitoring of wind turbine blades". Thesis, Montana State University, 2012. http://etd.lib.montana.edu/etd/2012/meehan/MeehanE1212.pdf.

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Monitoring a structure's response to various loading conditions is essential to being able to predict catastrophic failure of the part. There are many types of sensors that have been developed to be able to accurately measure these important quantities. However, as the structure becomes thicker, it is important to monitor in more places than just the surface of the material. Composite materials, such as those used in the wind turbine industry, are typically built in layers, which lend themselves to having sensors embedded in the structure. Previous research had focused on how these embedded sensors affected the mechanical properties of the material, and this research continues on by utilizing the gages to monitor the strains developed in the material. An important aspect of the research was to be able to separate the mechanical strain from the thermal strains developed in the substrate. This was achieved by using advanced circuitry, and was confirmed by performing tensile and heating tests on both surface mounted and embedded sensors. From the data collected, it was shown that it was possible to separate out the mechanical and thermal strains.

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Wilson, Amanda C. "Equivalent initial flaw size model development for turbine blades using in-service data". Thesis, Georgia Institute of Technology, 2003. http://hdl.handle.net/1853/20006.

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Everitt, Stewart. "Developments in advanced high temperature disc and blade materials for aero-engine gas turbine applications". Thesis, University of Southampton, 2012. https://eprints.soton.ac.uk/348897/.

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The research carried out as part of this EngD is aimed at understanding the high temperature materials used in modern gas turbine applications and providing QinetiQ with the information required to assess component performance in new propulsion systems. Performance gains are achieved through increased turbine gas temperatures which lead to hotter turbine disc rims and blades. The work has focussed on two key areas: (1) Disc Alloy Assessment of High Temperature Properties; and (2) Thermal Barrier Coating Life Assessment; which are drawn together by the overarching theme of the EngD: Lifing of Critical Components in Gas Turbine Engines. Performance of sub-solvus heat treated N18 alloy in the temperature range of 650°C to 725°C has been examined via monotonic and cyclically stabilised tensile, creep and strain controlled low cycle fatigue (LCF) tests including LCF behaviour in the presence of a stress concentration under load-control. Crack propagation studies have been undertaken on N18 and a particular super-solvus heat treatment variant of the alloy LSHR at the same temperatures, in air and vacuum with 1s and 20s dwell times. Comparisons between the results of this testing and microstructural characterisation with RR1000, UDIMET® 720 Low Interstitial (U720Li) and a large grain variant of U720Li have been carried out. In all alloys, strength is linked to a combination of γ' content and grain size as well as slow diffusing atoms in solid solution. High temperature strength improves creep performance which is also dependent on grain size and grain boundary character. Fatigue testing revealed that N18 had the most transgranular crack propagation with a good resistance to intergranular failure modes, with U720Li the most intergranular. Under vacuum conditions transgranular failure modes are evident to higher temperature and ΔK, with LSHR failing almost completely by intergranular crack propagation in air. For N18 significant cyclic softening occurs at 725°C with LCF initiation occurring at pores and oxidised particles. An apparent activation energy technique was used to provide further insights into the failure modes of these alloys, this indicating that, for N18 with 1s dwell, changes in fatigue crack growth rates were attributed to static properties and for LSHR, with 20s dwell in air, that changes were attributed to the detrimental synergistic combination of creep and oxidation at 725°C. Microchemistry at grain boundaries, especially M23C6 carbides, plays an important role in these alloys. Failure mechanisms within a thermal barrier coating (TBC) system consisting of a CMSX4 substrate, PtAl bond coat, thermally grown oxide (TGO) layer and a top coat applied using electron beam physical vapour deposition have been considered. TGO growth has been quantified under isothermal, two stage temperature and thermal cyclic exposures. An Arrhenius relation was used to describe the TGO growth and produce an isothermal TGO growth model. The output from this was used in the QinetiQ TBC Lifing Model. Thermo-mechanical fatigue test methods were also developed including a novel thermocouple placement permitting substrate temperature to be monitored without disturbing the top coat such that the QinetiQ TBC Lifing Model could be validated. The importance of material, system specific knowledge and performance data with respect to a particular design space for critical components in gas turbine engines has been highlighted. Data and knowledge regarding N18, LSHR and TBC systems has been added to the QinetiQ’s databank enhancing their capability for providing independent advice regarding high temperature materials particularly in new gas turbine engines.

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Lane, Christopher John Leslie. "The development of a 2D ultrasonic array inspection for single crystal turbine blades". Thesis, University of Bristol, 2011. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.651312.

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The aim of this thesis is to design and evaluate a non-destructive evaluation (NDE) system for the inspection of single crystal turbine blades. Turbine blades are the components within jet-engines that convert the hot, high-pressure gas exiting the combustion stage into mechanical power. During operation, these components are highly stressed and are surrounded by extremely high gas temperatures. As such, there is the potential for defects to initiate in-service. One way to ensure the structural integrity of these engine components is by periodically inspecting them for defects. The ability of the inspection to be performed in situ is highly advantageous, as this eliminates the cost and time delay associated with removing the turbine blades from the engine prior to inspection. A 20 ultrasonic phased array system was chosen for this project, as these systems can perform rapid volumetric inspections whilst being portable enough to be used in situ. Modem turbine blades are manufactured from single crystal nickel-based superalloys for the excellent mechanical properties these materials exhibit at elevated temperatures. However, these materials are elastically anisotropic. The propagation of ultrasonic waves through anisotropic materials is far more complex than the isotropic case. This causes significant difficulties when inspecting anisotropic single crystal components with ultrasonic arrays. Therefore, analytical models are developed to predict the propagation of ultrasonic waves in anisotropic materials. These models are used to correct an ultrasonic imaging algorithm to account for the anisotropic behaviour. To implement the corrected algorithm effectively, the orientation of the crystal in the component under inspection must be known. Therefore, crystallographic orientation methods using 20 ultrasonic arrays are developed and evaluated. The corrected algorithms and crystallographic orientation methods are used to develop an in situ 20 ultrasonic array inspection for a specific high-pressure single crystal turbine blade. The inspection is designed to detect and size cracking in the root section of the turbine blade. The developed inspection system is fully evaluated in a quantitative manner for its defect detection sensitivity and sizing capability.

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Doorly, Jane E. "The development of a heat transfer measurement technique for application to rotating turbine blades". Thesis, University of Oxford, 1985. http://ora.ox.ac.uk/objects/uuid:36bbf5b6-8978-4aae-920e-06ce0b96194e.

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The successful design of a long-lived and efficient gas turbine engine requires a good knowledge of the thermal and aerodynamic performances of the components of the turbine. Of particular importance, is the heat transfer rate from the hot gases to the cooled turbine blades, since this limits the maximum turbine entry temperatures which can be obtained. Much gas turbine research is concentrated on experimental modelling and measurements to assist in the development of improved theoretical prediction techniques. The difficulties of instrumenting fully rotational rigs, which are necessary for a full understanding of the complex three dimensional flow in the turbine, have, however, to a large extent, limited most experimental research to stationary facilities. A technique is described which will allow heat transfer rate measurements to be made on fully rotating test facilities using mutlilayered model turbine blades comprising an electrical insulator on a metal base. An accurate and computationally efficient method for determining the surface heat flux to a multi-layered model turbine blade is developed theoretically, together with a method for calibrating the thermal properties of the multi-layered system. This method allows the existing successful heat flux measurement technique, which utilises electronic analogue circuitry in conjunction with thin film surface thermometers on a model made from a thermal insulator, to be extended for application to multi-layered models. The production of test models by the application of a vitreous enamel (as an electrical insulator), to a mild steel, is identified as the most suitable coating technique for experimental application. Radiant and wind tunnel testing of multi-layered cylindrical models are described, which confirm that the method is both practical and accurate.

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Hu, Dawei. "Development of the epoxy composite complex permittivity and its application in wind turbine blades". Thesis, Queen Mary, University of London, 2010. http://qmro.qmul.ac.uk/xmlui/handle/123456789/540.

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Offshore wind farm structures may have the potential to affect marine navigation and communication systems by reflecting radar signals. With ever increasing size of wind turbines it is necessary to better understand the influence of radar signals on wind turbine blades in order to minimise the radar reflecting potential. One possible way of reducing radar reflection is to use radar absorbing materials. In this thesis, epoxy composite materials reinforced with five different types of nano-size additives: carbon nanotubes (CNTs), carbon blacks (CBs), silver, tungsten carbide and titanium oxide are manufactured and tested to investigated their potential as wind turbine blade material that absorb radar signals. Nanoadditives/epoxy composites with additives content ranging from 0.05-1 wt. % were fabricated by a simple cast moulding process. The nanoadditives were dispersed in the epoxy resin by sonication method. The degree of nanoadditives dispersion was observed by examining the surface of the composite materials using scanning electron microscope (SEM). Complex permittivity of the nanoadditives/epoxy composites was studied using a free wave transmittance only method at a frequency range of 6.5-10.5 GHz. The effect of the percolation threshold of the direct current conductivity on the composite permittivity was analysed and discussion. In order to get a better insight in the importance of the results they were compared to existing models (Maxwell- Garnett, Bruggeman, Bottcher, Lichtenecker and Lichtenecker-Rother). A new model based rule of mixtures is developed to predict the complex permittivity of the composite. A model of wind turbine rotor blade made of the nanoadditives/epoxy composite was developed using Comsol-multiphysics software. The data obtained from the experimental work was inputted in to the model to generate result of backscattered energy verses composite permittivity as a function of nanoadditives content. A decrease in backscattered energy was noticed with increasing nanoadditives content. The results demonstrate that radar reflecting signals will be significantly reduced by incorporating nanoadditives in the composite materials.

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Al-Qabandi, Osama. "Development of cost effective polymer composites for wind turbine blades with improved mechanical properties". Thesis, Glasgow Caledonian University, 2016. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.700991.

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Saint-Marc, Jean-Charles. "Development of a ballistic hybrid fabric model for aeroengine fan blade containment application". Thesis, Université Laval, 2012. http://www.theses.ulaval.ca/2012/28630/28630.pdf.

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Ce mémoire présente les travaux de recherche effectués au sein du département de Génie Mécanique de l’Université Laval dans le cadre du projet « Impact modeling of Composite Aircraft Structure », IMCAS du Consortium de Recherche et d’Innovation en Aérospatiale (CRIAQ). Le but de ces travaux était de créer une loi de comportement pour les composites tissés sec mous et de les implanter dans un élément coque reproduisant le comportement dynamique d’un croisement de fibres dans un pli typique sous impact balistique et en fonction de certains paramètres géométriques propres au tissé. La création d’une loi de comportement de l’usager dans le logiciel d’analyse par éléments finis Abaqus a été nécessaire pour mener à bien ce projet. La méthodologie de développement de la sous-routine de l’usager, qui définit le matériau tissé et est utilisée en conjonction avec l’élément shell S4R, est basée sur les récents travaux de Grujicic et al (1) et Shahkarami et al (2). La validation de ce modèle a été réalisée en vérifiant la validité de sa réponse à certaines sollicitations rencontrées dans des études simples d’impact. Le résultat final de ces tests numériques d’impact a permis de démontrer que nous obtenons des résultats similaires à ceux de Shahkarami pour les mêmes paramètres d’expérimentation. Enfin, après cette dernière validation, nous avons appliqué l’outil développé à l’étude, en dynamique explicite, de l’impact d’une pale de soufflante sur un caisson de confinement hybride. Ce caisson est composé d’une première couche intérieure en coque métallique et sur laquelle s’empilent plusieurs couches de kevlar. Tout au long de ce mémoire, nous avons détaillé toutes les hypothèses, les démarches et les outils utilisés pour réaliser ce travail. Nos résultats montrent finalement qu’il est possible de reproduire les phénomènes physiques à une échelle méso-mécanique lors d’un impact haute vitesse sur un matériau composite tissé multicouche tout en minimisant le temps de calcul nécessaire.
This thesis presents the work that has been carried out inside the Mechanical Engineering Department of Laval University within a CRIAQ project related to Impact Modeling of Composite Aircraft Structure (IMCAS). The main goal of this work was to develop a dry fabric model for ballistic impact application and to implement it into a shell element capable of reproducing the dynamic behavior of a yarn crossover point with due account of some specific geometric and material parameters. The development of a material user subroutine (VUMAT user subroutine) was necessary to carry out this project. The methodology employed for the development of the user subroutine to be used with the S4R shell element available in Abaqus is based upon the works of Grujicic et al (1) and Shahkarami et al (2). The validity of the mesomechanical model created was carried out in order to assess the accuracy of its behavior under elementary loadings. Subsequently, using the same parameters to set up the analysis, the developed model has been applied in simple impact problems in Abaqus to demonstrate that we are able to obtain the same results as in the work of Shahkarami (2) used as a reference. Finally, after this last validation, the model is used in the impact study of an aeronautical engine’s fan blade containment problem using a hybrid casing. In our problem the casing’s inner shell is metallic and multiple Kevlar fabric layers are wrapped around it to contribute to the energy absorption and containment of the fan blade debris released outward at high speed. In this thesis all the assumptions, process and tools necessary to carry out every analysis have been described in details. Our results demonstrate that it is possible to capture the physical phenomenon happening at the yarn’s mesoscopic level during a high-velocity impact on a dry fabric while minimizing the computation time.

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Charles, Amal Prashanth, i Taylor Claudio Alexander Gonzalez. "Development of a Method to Repair Gas Turbine Blades using Electron Beam Melting Additive Manufacturing Technology". Thesis, KTH, Industriell produktion, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-202367.

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This study focuses in using the electron beam melting additive manufacturing process to develop a framework to repair high performance gas turbine blades. These are currently fabricated using highly engineered super alloys, more specifically Inconel 738LC. The thesis focusses on the research on the current production methods of gas turbine blades, the operating environment inside the gas turbine, the most common failure modes as well as current methods of blade repair. This investigation includes studying the methods of production of metallic powders and the alloying effects of different elements in our required powder. A brief analysis was made to determine the economic viability for the usage of AM technology for mass production, and a proposition has been developed for the repair of turbine blades using additive manufacturing.

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Yun, Jinsik. "Development of Structural Health Monitoring Systems Incorporating Acoustic Emission Detection for Spacecraft and Wind Turbine Blades". Thesis, Virginia Tech, 2011. http://hdl.handle.net/10919/42507.

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Structural Health Monitoring (SHM) is the science and technology of monitoring and can assess the condition of aerospace, civil, and mechanical infrastructures using a sensing system integrated into the structure. SHM is capable of detecting, locating, and quantifying various types of damage such as cracks, holes, corrosion, delamination, and loose joints, and can be applied to various kinds of infrastructures such as buildings, railroads, windmills, bridges, and aircraft. A major technical challenge for existing SHM systems is high power consumption, which severely limits the range of its applications. In this thesis, we investigated adoption of acoustic emission detection to reduce power dissipation of SHM systems employing the impedance and the Lamb wave methods. An acoustic emission sensor of the proposed system continuously monitors acoustic events, while the SHM system is in sleep mode. The SHM system is evoked to perform the SHM operation only when there is an acoustic event detected by the acoustic emission sensor. The proposed system avoids unnecessary operation of SHM operations, which saves power, and the system is effective for certain applications such as spacecraft and wind turbine blades. We developed prototype systems using a Texas Instruments TMS320F2812 DSP evaluation board for the Lamb wave method and an MSP430 evaluation board for the impedance method.
Master of Science

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Raza, Mohsin. "Process development for investment casting of thin-walled components : Manufacturing of light weight components". Licentiate thesis, Mälardalens högskola, Innovation och produktrealisering, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:mdh:diva-27807.

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Manufacturing processes are getting more and more complex with increasing demands of advanced and light weight engineering components, especially in aerospace industry. The global requirements on lower fuel consumption and emissions are increasing the demands in lowering weight of cast components. Ability to produce components in lower wall thickness will not only help to reduce the cost of production but also help to improve the efficiency of engineering systems resulting in lower fuel consumption and lesser environmental hazardous emissions. In order to produce thin-walled components, understanding of mechanism behind fluidity as it is effected by casting parameters is very important. Similarly, for complex components study of solidification morphology and its effects on castability is important to understand. The aim of this work was to investigate casting of thin-walled test geometries (less than 2mm) in aero-space grades of alloys. The casting trials were performed to investigate the fluidity as a function of casting parameters and filling system in thin-walled sections. Test geometries with different thickness were cast and evaluated in terms of filled area with respect to casting parameters, ı.e. casting temperature and shell preheat temperature. Different feeding systems were investigated to evaluate effects of filling mode on castability. Similarly for complex components where geometries are very organic in shape, solidification morphology effects the quality of castings. Process parameters, that effect the solidification morphology were identified and evaluated. In order to develop a relation between defect formation and process parameters, solidification behaviour was investigated using simulations and casting trials. Similarly the effect of factors that influence grain structure and flow related defects were studied. It was observed that fluidity is affected by the mode of geometry filling in investment casting process. The filling mode also have different effect on defect formation. A top-gated configuration is strongly affected by casting parameters where as a bottom-gated configuration is more stable and thus fluidity is not significantly affected by variation in casting parameters. Less porosity and flow-related defects were observed in the bottom-gated system as compared to top-gated system. In the study about casting defects as affected by process parameters, it was observed that shell thickness is important to avoid interdendritic shrinkage. It was observed that the increased shell thickness induces a steeper thermal gradient which is essential in order to minimize the width of the mushy zone. It was also observed that a slower cooling rate along with a steeper thermal gradient at the metal-mould interface not only helps to avoid shrinkage porosity but also increases fill-ability in thinner sections. The work presented here is focused on the optimization of process parameters, in order, for instance, to improve castability and reduce the casting defects in investment casting process. The work, however, does not focus on externally influencing the casting conditions or modifying the casting/manufacturing process. The future work towards PhD will be focused on externally improving the casting conditions and investigating other possible route of manufacturing for thin, complex components.

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Utada, Satoshi. "Effect of a Prior Plastic Deformation during Heat Treatments on the Mechanical Properties of Ni-Based Superalloys for Turbine Blade Application Evolution of superalloy for turbine airfoil and development of recycling technology Platinum containing new generation nickel-based superalloy for single crystalline application Tensile, low cycle fatigue and very high cycle fatigue characterizations of advanced single crystal nickel-based superalloys Creep Property and Phase Stability of Sulfur-Doped Ni-Base Single-Crystal Superalloys and Effectiveness of CaO Desulfurization Evaluation and comparison of damage accumulation mechanisms during non-isothermal creep of cast Ni-based superalloys". Thesis, Chasseneuil-du-Poitou, Ecole nationale supérieure de mécanique et d'aérotechnique, 2020. http://www.theses.fr/2020ESMA0019.

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Les superalliages monocristallins base Ni sont utilisés pour la conception des aubes de turbines en raison de leur excellente durabilité à haute température. Lors de la production d'une aube de turbine, une déformation plastique (DP)inattendue peut être introduite dans le matériau. Dans cette étude, les matériaux monocristallins ont été pré-déformés entre les traitements thermiques de mise en solution et de revenu pour simuler la DP pouvant être rencontrée lors des étapes de production. Des tests mécaniques sur les matériaux pré-déformés ont été effectués pour comprendre l'effet de cette DP.Au cours des traitements thermiques de revenu du superalliage monocristallin AM1 pré-déformé, un grossissement des précipités γ′ plus rapide et une nucléation accélérée de pores ont été observés à proximité des bandes de glissement introduites lors de la DP à température ambiante. Au cours de la déformation par fluage de l’AM1 pré-déformé dans des conditions de haute température/basse contrainte (≥ 950 °C), les bandes à microstructure grossière sont des sites préférentiels d’accumulation du dommage de fluage induit par diffusion, induisant de la recristallisation et une réduction drastique des propriétés de fluage. Dans des conditions de basse température/haute contrainte (≤ 850 °C), le cisaillement de la microstructure est facilité dans les bandes à microstructure grossière et il réduit également les propriétés de fluage.La recristallisation n'est pas été observée dans des ces conditions de fluage à basse température car les mécanismes diffusifs sont ralentis. Ces résultats ont été confirmés via des essais de fluage sur des matériaux pré-déformés suivant différent chemin de pré-déformation (température, position de la DP dans le cycle thermique…). Le superalliage monocristallin CMSX-4 Plus a été testé de manière similaire à l'AM1 pour comprendre l'effet de la composition chimique. L'effet de la DP sur la microstructure de l'alliage est plus limité pour cet alliage par rapport à celui sur l’AM1. Par conséquent, la pré-déformation n'a pas montré de chute de la durée de vie pour le CMSX-4 Plus à des températures inférieures à 1050 °C. Par contre, pendant le fluage de CMSX-4 Plus à 1150 °C, la pré-déformation a montré un impact spectaculaire sur la durée de vie et la ductilité via les mêmes mécanismes que ceux observés pourl’AM1 à 1050 °C.Afin de régénérer les propriétés des superalliages monocristallins pré-déformés, un traitement thermique de restauration a été ajouté après la DP. Le traitement de restauration a permis de restaurer la microstructure après la DP à température ambiante avec succès, et les propriétés de fluage des matériaux restaurés sont équivalentes à celles de l'AM1 et duCMSX-4 Plus vierges de pré-déformation
Ni-based single crystal (SX) superalloys are used for turbine blade applications because of their high-temperature durability. During the production of a turbine blade, unexpected plastic deformation (PD) can be introduced to the material. In this study, SX materials were pre-deformed in between solution and aging heat treatments to mimic PD during production. Mechanical tests on the pre-deformed materials have been performed to understand the effect of the prior PD.During aging treatments of pre-deformed AM1 SX superalloy, faster coarsening of γ′ precipitates and enhanced void nucleation were observed in the vicinity of slip bands which were introduced by PD at room-temperature. During creep deformation of pre-deformed AM1 at high temperature/low stress conditions (≥ 950 °C), the microstructure coarsened bands act as diffusion induced creep damage accumulating paths, further triggering recrystallization and resulting in drastic reduction of creep properties. At low temperature/high stress conditions (≤ 850 °C), microstructure shearing was facilitated in the microstructure coarsened band and it decreased creep properties. Recrystallization was not observed at lower temperature creep because the diffusion damage was suppressed. These relationships have been explained by creep tests on pre-deformed materials prepared by different pre-deformation temperatures and heat treatment procedures.CMSX-4 Plus SX superalloy was tested similarly to AM1 to understand the effect of the chemical composition. Effect of pre-deformation on alloy’s microstructure was mild in CMSX-4 Plus compared to that in AM1. Therefore, the predeformation did no exhibit large creep life debit in CMSX-4 Plus at temperatures lower than 1050 °C. However, during creep of CMSX-4 Plus at 1150 °C, pre-deformation presented huge impact on creep life and ductility by the same mechanisms as the ones observed for AM1 at 1050 °C.In order to restore properties of pre-deformed SX superalloys, rejuvenation heat treatment was added after PD.Rejuvenation treatment successfully restored microstructure after PD at room-temperature, and creep properties of rejuvenated specimens were shown to be equivalent to that of original AM1 and CMSX-4 Plus without PD

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Charlesworth, Chris. "Ultrasonic phased array testing in the power generation industry : novel wedge development for the inspection of steam turbine blades roots". Thesis, University of Warwick, 2011. http://wrap.warwick.ac.uk/49401/.

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The thesis presented herein comprises of the work undertaken to research novel methods of Phased array ultrasonic inspection of complex steam turbine blade roots as found in the power generation industry. The research was conducted as part of the Engineering Doctorate scheme, administered by the Research Centre for Non-Destructive Evaluation (RCNDE), in conjunction with RWE npower and the University of Warwick. Steam turbine blades, and in particularly last stage blades of low pressure steam turbines, are amongst the most highly stressed components on a power generating plant. Two of the most common blade root fixing types include ‘curved axial entry fir tree roots’ (CAEFTR), and axial pinned roots, both of which are prone to cracking due to the high stresses to which they are subjected under operating conditions. Failure of the blade root fixings of such components, leading to the release of the blades, has historically led to the catastrophic failure and destruction of the whole turbine; the cost of collateral damage to plant components and the loss in generating income are seconded only by the risk these failures pose to life. Due to the high price of failure, NDT plays a critical part in the support and management of engineering maintenance, offering insight into the condition and integrity of turbine components through regular planned inspection regimes. It will be shown in this thesis how the invention of a novel continuous wedge, used to refract ultrasound into the critical regions of the blade roots, has significantly improved the ability to detect defects. Combined with the development of bespoke scanning frames these wedges facilitate the efficient and accurate acquisition of scanned data to assess the integrity of the component. By combining the latest reverse engineering, modelling and simulation tools with novel application of rapid prototyping, the author has been able to demonstrate significant reduction in design cycles whilst improving accuracy, sensitivity and repeatability of the applied inspections. Furthermore, application of this design philosophy has led to the development of inspection techniques which have facilitated the inspection of remote regions of the blade roots where manual access is limited or impossible. The developments and techniques invented during this research have been successfully deployed across numerous RWE npower and customer projects, leading to estimated savings in excess of £1m.

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Azmi, Mohd Shahrul Nizam. "Development of a strain gauge for monitoring system that can be applied to wind turbine blades stress testing in the laboratory". Thesis, Azmi, Mohd Shahrul Nizam (2018) Development of a strain gauge for monitoring system that can be applied to wind turbine blades stress testing in the laboratory. Honours thesis, Murdoch University, 2018. https://researchrepository.murdoch.edu.au/id/eprint/41904/.

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This document will provide information about the approach that used to get the reading information from the wind blade in laboratory. This part is mainly focusing on getting a signal reading from a strain gauge to Arduino. The development of this project was based upon the requirement to study the effect of the turbulence that might affect the wind turbine blade. The investigation of the load that the blade experienced will then be analysed to ensure the wind turbine is able to maximise the production and also take into account the safety issues that arise according to the standard after project design constructing and implementation occurred in the real system. This document will show the details of the instruments and the design approach that enabled capturing of the load data in a controlled environment. In field testing, strain gauges on the root of turbine blades capture the blade flapwise and edgewise loading. This project focuses on development of a monitoring system to capture strain gauge data. To simplify the experiment, strain gauge are loaded in the controlled environment of a laboratory. A programme and a setup to implement this project has been developed at this. A results gathered in Chapter 4 Result and Analysis documented throughout this stage will be more reliable, proven and realistic if the content of this document is demonstrated on the real wind blade that located in Pilot Plant area. However, to develop the full functionality of this project, a person also needs to understand the transmitter and receiver aspects of the project. The establishment of the basic data logging for the main project was achieved based on the result collected.

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Yu, Luo Sheng, i 羅勝禹. "Development of Small Vertical Axis Wind Turbine Blade". Thesis, 2013. http://ndltd.ncl.edu.tw/handle/44296369380828706717.

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碩士
建國科技大學
機械工程系暨製造科技研究所
101
A small vertical axis wind turbine (SVAWT) with lift-type and drag-type blades were designed and tested in this paper. In order to improve the performance of the SVAWT with low start up wind speed, the struts connecting lift-type blades and rotating axis were designed as drag-type blades. The cross section of lift-type blades using in the SVAWT was NACA0018 for maintaining the rotating speed under higher wind speed. The parts of the SVAWT including blades and struts were designed by computer-aided design software and manufactured with the aid of computer-aided manufacturing, rapid prototyping and rapid tooling. The SVAWT was tested in a wind tunnel with the wind speed ranging from 2 to 7 m/sec. The test results containing rotating speed and torque were recorded to evaluate the performance of the SVAWT. The results showed that the drag-type blade could start up the SVAWT wind low speed, but would reduce the rotating speed under higher wind speed.

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LI, YUN-LIN, i 李運霖. "Study on Wind Turbine Blade Models Development and Reality Fabrication". Thesis, 2017. http://ndltd.ncl.edu.tw/handle/m8xb6j.

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碩士
建國科技大學
電機工程系暨研究所
105
ABSTRACT The global wind power systems at present include two main types: (1) horizontal axis wind turbine (HAWT) system, and (2) vertical axis wind turbine (VAWT) system. This paper studied on wind blade models development and reality manufacture. First, the researcher collected and read related literature of wind power systems. Second, the researcher studied on HAWT blade (including one traditional model and eight innovative models) and VAWT blade (including one traditional model and eight innovative models), and adopted the methodologies of Bionics and TRIZ to innovate. There are three VAWT blades used TRIZ theory, eight HAWT blades and five VAWT blades used Bionics. Third, the researcher used 3D direct modeling software (e.g. SpaceClaim, SolidWorks and AutoCAD) to draw the figures, and used RP 3D printer (FORTUS 360mc) to manufacture the wind blade models. Fourth, the researcher also used an experiment device (WINDTRAINER) to propel and measure the voltages, currents of the wind blade models, adjusted the wind speed (4 m/s~12 m/s), compared their watts (Pa) and rotor power coefficient (Cp). Thus, the researcher can find the higher efficient wind blades of HAWT and VAWT types. The researcher found the best Cp value of HAWT blade is Bentley type, the better Cp value is four-leaved clover type; and the best Cp value of VAWT blade is Tai-Chi spiral type, the better CP value is Taiwan shape type. The other, the better Cp value of commercial advertisement for attracting the customers are Bentley type and Taiwan shape type. The baseball set shape wind blade is quite attractive, but its Cp value needs to be improved. These customer oriented innovative wind blades are designed to go beyond the thinking of the traditional wind blade models. The next, in the area of reality manufacture, we purchased and installed one 300W type VAWT power system (including an arc type blade, a Spiral type blade, a generator, a cylinder about 3 meters in height, a controller, two batteries, and a load of LED streetlamp). We used one PC and its monitor package to test and analyze this system functions. The wind power system got more watts (Pa) during the winter in 2014 typhoon Soudelor and typhoon Dujuan and the winter in 2015,and typhoon Nepartak and the winter in 2016. Finally, this research result is valuable in teaching and R&D of wind power generation. Furthermore, we use these innovative wind blades to take part in some international invention exhibitions and won some prize that can win the honor for CTU.

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Yanto, Harki Apri, i 王子綜. "Development of the Multi-Blade, Drag-Type, Vertical Axis Wind Turbine". Thesis, 2014. http://ndltd.ncl.edu.tw/handle/z48ucv.

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博士
國立臺灣科技大學
機械工程系
102
In this study, the development of a light-weight, simple design, and high economic value multi-blade, drag-type, vertical-axis wind turbine (MVAWT) is carried out by combining the design, mathematical model, computational fluid dynamic, fabricating, and experimental means as a complete research scheme. At first, the design process is approached by the evidence of a huge amount of negative drag force during the upwind condition for the drag-type, vertical-axis wind turbine. An automatic blade-flipping mechanism design is developed with the purpose to minimize the drag force on the upwind condition. Followed by that, fabrication and installation of a full-scale small size MVAWT is conducted to observe the functional of blade flipping mechanism and the wind turbine performance. The complete experimental work follows the IEC61400-12 standard procedure for ensuring the accurate experimental data. Besides, an electric generator, off-line loading system, meteorology mast system, and real-time data acquisition system (DAQ) are installed as a sophisticated wind turbine measuring system, where all environmental information and power data from sensors and generator on the platform are recorded and transferred to the computer automatically. Afterwards, the data processing and in-depth analysis on the experimental outcomes are executed via the established computer program. Consequently, the on-site performance of wind turbine/generator system is attained in an automatic and systematic manner. Moreover, for providing sufficient data and its accuracy, statistic concept is enforced to judge whether the test data are appropriate for considering in the data-processing procedure. Also, mathematic model and CFD simulation are conducted to estimate the torque distribution and flow characteristics during the operation of MVAWT. By focusing on the flow interaction around the blade, it can be concluded that the autonomous blade-flipping mechanism generate several important phenomenon, such as less drag force during the upwind condition, a sufficient thrust force to gain torque during the operation in low wind speed. In summary, combine with experimental data and numerical simulation results, this systematic and rigorous study on MVAWT is presented and can be served as a stepping stone for executing the R&D in harvesting wind energy as an alternative energy source.

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Epaarachchi, Jayantha Ananda. "The development and testing of a new fatigue life procedure for small composite wind turbine blades incorporating new empirical fatigue life prediction and damage accumulation models for glass fibre reinforced plastics". Thesis, 2002. http://hdl.handle.net/1959.13/1312474.

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Research Doctorate - Doctor of Philosophy (PhD)
The work in this thesis is concerned with developing a suitable fatigue life evaluation procedure for the blades of small wind turbines. Detailed strain gauge measurements from the blade of an operating 2.5m long composite-constructed blade were used to establish a relationship between upstream wind speed and blade response. A blade fatigue test procedure has been developed using historical wind data and the wind speed/blade response relationship; a detailed description of the methodology and procedure used is documented in this thesis. Existing empirical models to determine the fatigue life of glass-fibre reinforced composites were found to be inadequate for composite-constructed small wind turbine blades as they do not adequately address the effects of load frequency and stress ratio, and cannot be easily extended to address cumulative fatigue life calculations. A model has been developed which overcame these limitations, an is detailed in this thesis. A fatigue test rig has been designed and built to test blades 2.5m in length and has been used successfully to evaluate the fatigue life of a composite blade using the developed fatigue test procedure. The Wind Energy Group at the University of Newcastle had a 5kW prototype wind turbine at Fort Scratchley, Newcastle. Here one of the turbine's composite blades was instrumented with strain gauges with signals acquired simultaneously with those representing wind speed and direction, turbine direction and turbine generator power. Results show that the blade does not respond instantaneously to all changed in wind speed but follows the wind profile. A detailed finite element model of this blade was solved for load due to aerodynamic pressures and blade rotation. Predictions from the model were found to be in good agreement with the measurements. Comprehensive meteorological data were obtained through the Australian Bureau of Meteorology for 18 sites. Here the maximum and mean wind speeds were presented for a 30 minuted time increment with data acquired and averaged over a 10 minute time period in each increment with data acquired and averaged over a 10 minuted time period in each increment. This wind data was found to fit to a Weibull distribution. The data were also rainflow counted to isolate blade fatigue cycles. The detailed wind data acquired at 0.5Hz rate from the turbine test site at Fort Scratchley were also rainflow counted to determine the blade fatigue cycles in 10 minute sampling periods. From these data, a relationship between the average and maximum wind velocity and the number of wind cycles was determined. A method has been developed, and is detailed in this thesis, to determine all likely blade loading cycles using the Bureau's data and the Fort Scratchley data. The worst-case yearly fatigue loading spectrum was determined to have a total of 1803705 cycles representing stress levels for wind velocities between 1 m/s to 20 m/s and binned under stress ratios between 0 and 0.9 inclusive. This loading cycle was used to test the 2.5m composite. An empirical model for the fatigue life of glass-fibre reinforced plastic composites under various stress ratios and loading frequencies has been proposed. The model has been tested with fatigue test data from the literature as well as from various research laboratories. The model shows close agreement to all test data. This model was extended to predict cumulative fatigue damage and to overcome limitations of traditional cumulative fatigue rules such as Miner's rule. Predictions from this cumulative fatigue model were in good agreement with cumulative fatigue data obtained from the literature and the results of experiments performed by the author. The fatigue properties for the composite materials used in the wind turbine blade were determined from standard fatigue tests. Using a minimal about of experimental fatigue data, the proposed fatigue life of the blade for any loading spectrum. This cumulative fatigue model was found to perform better than traditional cumulative fatigue models. A mechanically operated test rig where the load on the blade was applied through a crank-level mechanism has been designed and built to test the 2.5m long wind turbine blades using the developed load spectrum. This test rig can apply blade loading at a maximum frequency of around 3Hz. Fatigue testing of the 2.5m composite blade shows that the material's properties continuously degradation with time. Predictions of blade fatigue life using material properties based on uni-axial fatigue data were found to be significantly lower than those based on flexural fatigue data. This disparity was found to be due to the difference between the stress state of the blade's critical section under full scale fatigue test conditions and the stress state under standard fatigue test conditions. Furthermore it was analytically shown that the blade's life span predictions were unaffected by the loading sequence.

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Jian-Yung, Kao, i 高建勇. "The development of an automatic image system for turbine blade defects inspection". Thesis, 2000. http://ndltd.ncl.edu.tw/handle/47052946531734384666.

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Kai-ChingChou i 周塏晉. "Development of blade & tower structure and monitoring system for the 1KW wind turbine". Thesis, 2011. http://ndltd.ncl.edu.tw/handle/63452927411097686187.

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Abdelrahman, Ahmed. "Development of a Wind Turbine Test Rig and Rotor for Trailing Edge Flap Investigation". Thesis, 2014. http://hdl.handle.net/10012/8454.

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Alleviating loads on a wind turbine blades would allow a reduction in weight, and potentially increase the size and lifespan of rotors. Trailing edge flaps are one technology proposed for changing the aerodynamic characteristics of a blade in order to limit the transformation of freestream wind fluctuations into load fluctuations within the blade structure. An instrumented wind turbine test rig and rotor were developed to enable a wide-range of experimental set-ups for such investigations. The capability of the developed system was demonstrated through a study of the effect of stationary trailing edge flaps on blade load and performance. The investigation focused on measuring the changes in flapwise bending moment and power production for various trailing edge flap parameters. The blade was designed to allow accurate instrumentation and customizable settings, with a design point within the range of wind velocities in a large open jet test facility. The wind facility was an open circuit wind tunnel with a maximum velocity of 11m/s in the test area. The load changes within the blade structure for different wind speeds were measured using strain gauges as a function of flap length, location and deflection angle. The blade was based on the S833 airfoil and is 1.7 meters long, had a constant 178mm chord and a 6o pitch. The aerodynamic parts were 3D printed using plastic PC-ABS material. The total loading on the blade showed higher reduction when the flap was placed further away from the hub and when the flap angle (pitching towards suction side) was higher. The relationship between the load reduction and deflection angle was roughly linear as expected from theory. The effect on moment was greater than power production with a reduction in moment up to 30% for the maximum deflection angle compared to 6.5% reduction in power for the same angle. Overall, the experimental setup proved to be effective in measuring small changes in flapwise bending moment within the wind turbine blade.

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CASTORRINI, ALESSIO. "Development of CAE tools for fluid-structure interaction and erosion in turbomachinery virtual prototyping". Doctoral thesis, 2017. http://hdl.handle.net/11573/940503.

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The work presented in this thesis is based on the development of advanced computer aided engineering tools dedicated to multi-physics coupled problems. Starting from the state of the art of numerical tools used in virtual prototyping and testing of turbomachinery systems, we found two interesting and actual possible developments focused on the improved implementation of fluid-structure interaction and material wearing solvers. For both the topics we will present a brief overview with the contextualization on the industrial and research state of the art, the detailed description of mathematical models (Chapter 2), discretized (FEM) stabilized formulations, time integration schemes and coupling algorithms used in the implementation (Chapter 3). The second part of the thesis (Chapter 4-7) will report some application of the developed tools on some latest challenges in turbomachinery field as rain erosion and load control in wind turbines and non-linear aeroelasticity in large axial fans.

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Sharath, S. "Supercritical CO2 Power Cycles and Turbomachinery Development for Renewable Energy and Waste Heat Recovery". Thesis, 2021. https://etd.iisc.ac.in/handle/2005/5553.

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Supercritical carbon dioxide (sCO2) power cycles have transitioned from the kilowatt level pilot facilities to the megawatt level demonstration plants. Theoretical studies and commercial benefits associated with sCO2, such as high efficiency, compact turbomachinery, fuel agnostic heat source, zero or minimum water usage, reduced footprint, cost, etc., have been comprehensively documented. Currently, with renewable energy gaining traction, the baseload steam and gas turbines are forced to operate as peak load plants with the need for increased operational flexibility. Therefore, the industrial power production segment (< 150 MW) is slowly gaining increasing attention worldwide, emphasizing the utilization of sCO2 technology. Waste Heat Recovery (WHR) is another important segment receiving wide attention as it contributes to energy efficiency in an increasingly climate-conscious world. Industrial WHR such as those from steel, cement, process plants, and gas turbine (GT) exhaust is equivalent to 63% of global primary energy consumption. sCO2 plays a significant role in WHR due to higher cycle efficiency, smaller footprint, and eventual lower capital cost than alternate waste heat to power conversion systems. A significant number of the sCO2 cycle studies and pilot plants have focused on low ambient conditions (32 °C compressor inlet) and higher turbine inlet temperature 'TIT' (>600 °C) for renewable energy applications. The ambient temperature influence is not trivial in real gas cycles such as sCO2. A greater focus is placed in previous studies on GT exhaust heat for sCO2 WHR and almost insignificant work in Industrial WHR. This thesis addresses the crucial gaps by proposing a Recompression cycle for renewable power generation and a Simple Recuperated cycle for WHR with higher ambient temperature (>40 °C) and TIT within 600 °C. Despite the reduction in thermal efficiency, limiting TIT has significant benefits. It enables leveraging cost-effective industrial steam turbine technology while still addressing large segments of renewable energy and industrial WHR. The second part of the thesis focuses on sCO2 turbomachinery development and testing, with emphasis on the sCO2 turbine. Kilowatt level pilot facilities have focused on radial turbines that are not scalable above 5 MW, where axial turbines are needed. Presently, there is very little published research on megawatt-scale axial sCO2 turbine due to their proprietary nature. Additionally, the focus on axial turbine development has been mainly for high-temperature applications requiring a range of new technologies and materials to be proven. The work presented in this thesis is among the initial publications to describe in detail the sCO2 axial turbine and blade development. Best in class sCO2 turbine blade profiles have been developed by employing novel optimization methods and Q3D, 3D solvers. This is followed by validation of blade performance in a linear cascade Wind Tunnel (WT) test at Politecnico di Milano, Italy. Subsequently, CFD-based 3D loss tuned using experimental data is utilized in the in-house developed mean-line code coupled to an industry-standard throughflow solver to generate the turbine flowpath. The last part of the thesis proposes a new analytical optimization model for sCO2 Brayton cycles utilizing Jacobian transformations and real gas thermodynamics. The analytical model has vital utility in transient dynamic analysis and real-time control of power and refrigeration cycles. In summary, the research comprehensively covers sCO2 cycles, turbomachinery development, and analysis by considering practical conditions, including comparisons with operating steam turbine power plants. The research culminates with case studies describing the development of sCO2 cycle and turbomachinery for a 10 MW renewable power generation and a 15 MW steel coke oven plant industrial WHR.

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kuveya, Khanyisile Rose. "A study towards the development of the laser shock peening technology for an Eskom power station low pressure steam turbine blade application. To also compare the impact of laser shock peening without coating against shot peening treatment on 12%Cr steel". Thesis, 2018. https://hdl.handle.net/10539/26784.

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A dissertation submitted to the Faculty of Engineering and the Built Environment, University of the Witwatersrand, in fulfilment of the requirements for the degree of Master of Science in Engineering, under the supervision of Professor Claudia Polese,2018
The root section of a turbine blade is the most critical part as it forms the structural bond of the turbine blade to the shaft. If not maintained correctly the blade could fail catastrophically due to high and low cycle fatigue, stress corrosion cracking as well as corrosion fatigue. The sources of loading on the blades vary from normal operation, excitation of natural frequencies during transient occasions and overloads during statutory testing. Different surface modification technologies can be put in place to improve blades in-service performance. The present study is aimed at comparing previous results achieved from Shot Peening (SP) of an equivalent turbine blade to those achieved by Laser Shock Peening without coating (LSPwC).The SP data which is used for comparison is from the work and study done to optimise the SP of a 12Cr steel steam turbine blade. It is expected that LSPwC processing of the blade will result in a reduction in mean surface roughness (Ra), and deeper compressive residual stresses than the conventional SP processing. The focus of this investigation is also to determine the effects of LSPwC laser and processing parameters, such as laser intensity, laser spot size, coverage, water layer, and possibly laser wavelength on the X12CrNiMo12 high strength steel target material. Segments of an ex-service turbine blade, 20x20mm by 10mm thickness, processed at the CSIR National Laser Centre under various LSPwC parameters were analysed as follows: composition properties confirmed by spark tests; surface integrity assessed by SEM and 3D roughness mapping; microstructure; residual stress measurements by laboratory X-ray Diffraction. The experimental results helped in optimizing the LSPwC parameters for the X12CrNiMo12, before applying LSPwC to the more complex geometry of the blade root. This study then allowed for the determination of which peening process is most suited for turbine components.
XL2019

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Huang, Yu-Jen, i 黃裕仁. "Development of Control System of Hydraulic Testing Facility of Wind Turbine Blades". Thesis, 2006. http://ndltd.ncl.edu.tw/handle/94548727769951019991.

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碩士
大葉大學
機械工程研究所碩士班
94
The reserve of petroleum decreases gradually. The development of alternative energies is the most important topic internationally. Among alternative energies, the wind power is the most promising one. The power generating efficiency of a wind turbine depends on aerodynamic characteristics of its blades. Also, the serve life of blades affects the overall cost of power generated. Therefore, structure tests of blades to understand their behavior under loads become necessary. Hydraulic system has been used on lots of kinds of equipments generally. It has many advantages; such as it can provide greater strength and has smaller volume compared to other actuator systems. These advantages make the system become an essential part in industrial applications. In this study, we used a hydraulic system to provide loadings to a blade that simulate the actual wind loading on the blade during operations of a wind turbine. We developed a computer interface to the programmable logic controller that controls the hydraulic system, and then control several valves and hydraulic cylinders of the hydraulic power system to apply loadings to the blade. In the interface, we can control the hydraulic pressure, flow speed, cylinder position of the hydraulic system. An experimental setup for blade test of a 25 kW wind turbine system was designed and installed. Some limit load cases of the blade were also tested in this study.

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Wang, Shih-Chun, i 王識鈞. "Design and Development of Precision Miniature Twin-bladed Ultra High-speed Air Turbine". Thesis, 2012. http://ndltd.ncl.edu.tw/handle/71639867971690471148.

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博士
國立臺灣大學
機械工程學研究所
100
Research and development of this thesis is to investigate the performance and characteristics of precision miniature twin-bladed air turbines in an ultra-high-speed region. In order to improve the machining efficiency of ultra-precision and micro fabrication technology, a high speed spindle is essential for the miniature tools which widely applied in systems such as PCB drilling machines, micro fabrication machines, and dental handpieces, etc. To realize the performance in high speed region, the air driven turbine is verified to be more feasible than an electromagnetic actuator. Furthermore, the operational efficiency and quality of the high speed spindle are significantly influenced by the turbine impeller and its bearings, respectively. Through detailed configuration studies and performance analyses on diverse miniature turbine impellers, the efficiency-influential and quality-influential parameters have been derived. And based on optimization results, a novel type of twin-bladed impeller (TB-impeller) on air turbine, which consists of two parallel impellers with an angular offset, is developed. The offset twin impellers can efficiently and smoothly transform pneumatic energy into rotational energy. Therefore, steady driving force and less dynamic unbalance are easily achieved for reducing operational disturbances such as vibration, noise, and wear. By applying a finite element analytical method, the operational performance and quality of the new developed twin bladed impeller such as rotational speed, torque, vibration, and noise were analyzed for comprehending influences of the design parameters and the operational parameters. While the inlet diameter, the blade shape and its geometric parameters are the dominant design parameters; the inlet pressure ,mass flow rate, and the outlet pressure are the main operational parameters. Through the turbine impellers, the pneumatic energy can be transformed into operational energy in form of the flow field and the pressure distribution as well as the energy loss in form of turbulence. Also by integrating knowledge of production technology, a neat design of the turbine impellers suitable for automatic manufacturing processes is developed. And furthermore, through an elaborate layout of the flow guiding, a minimum rotational run-out can be effectively achieved without any complicate and costly machining processes. Consequently, it can significantly depress the stream noise and raise the operation lifetime of bearings. According to our experimental verification at the same inlet pressure, the free running speed, power efficiency, and torque of novel TB-impeller are 10 %, 10 %, and 15 % higher than traditional counterparts, respectively. And the stream noise can be reduced by 17 %. The developed miniature spindle with novel TB-impeller can efficiently realize high speed rotation with high free running speed, high torque, less vibration, and less noise. By its superior features, the developed twin-bladed impeller also broadens the application possibilities in high speed machining fields with high efficiency and fewer expenses.

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Wen, Ren-Fang, i 溫仁方. "The Design, Development and Testing of Small Wind Turbine Blades Changeable Angle of attack". Thesis, 2017. http://ndltd.ncl.edu.tw/handle/t69r5s.

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碩士
明道大學
材料與能源工程學系碩士班
105
In order to improve the energy shortage and global warming issues, people work heart to create a lot of renewable energy, in many renewable energy project, the technology of Wind Turbine is mature and have good economic efficiency. Wind Power Device grows very fast in the world, since 1990, the average value of annual growth is 25%, it will be stable to grow in the future and be the most important of energy, the Carbon reduction policy is one of the goals in our country to evolve renewable energy. Large Wind Turbine is saturated in development of Wind energy using effectiveness, but medium-small Wind Turbine has a lot of space for development, in order to develop and popularize medium-small wind turbine to the people, that is our purpose. Our design is a variable-angle blades using Hook’s Law spring to change the angle, the max speed can be more large, in high speed, our Axis can make the blade-angle stable in rated revolution to protect Generator, this design can make the blade and Generator more durable, design Anti strong winds Blade, lower damage for Blade and Generator also make the repairing expensed and cost lower, study safety structure and well-power of Small Wind Turbine in different wind speed to develop simple mechanical device. During the research, there are many parameters, so our research use actual test to record the result, when we got preliminary result, we joined “2016National wind energy and marine energy creative practice competition” in National Taiwan Ocean University, we earn very precious experience, and then we keep working hard and get better, joined “2016National college production innovation implementation competition” in National Changhua University of Education, we got Outstanding Award, we also had been invited to “2016Best Source Energy Technology creative exhibition” in National Science and Technology Museum. Had many kind of development experience, our research designed the wind turbine have a lot of affirmation, we have do well in security protection mechanism of Wind Turbine in variable axis and spring, the security protection mechanism turn on successfully in 8m/s with K=0.9 spring, according to the derivation of lab data, we predict the security protection mechanism is working in 11m/s with K=1.0 spring, the blades speed increase and revolution keeps stable, keep generating electricity stably in rated revolution, we also upgrade the power range of Wind Turbine in the safety situation, giving the wind turbine a good innovation and development.

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Yang, Chaochieh, i 楊超傑. "A Development Of Testing Platforms For Composite Blades Of Stackable Vertical Axis Wind Turbine". Thesis, 2011. http://ndltd.ncl.edu.tw/handle/67646624781762042665.

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碩士
大葉大學
工業工程與科技管理學系
100
We give careful consideration to energy development in Taiwan under the issues of energy shortage and environmental protection in today's world. Wind power has already become a great commercial value; it is cheap, clean and easy to be attained. However, the efficient executions of wind power and environmental protection policies have become the world's common goal. Wind turbines can be classified into two main categories, namely, horizontal axis and vertical axis wind turbines [HAWT and VAWT]. Especially for VAWT, it had no adequate engineering case to exploit and had no international standard to refer. Therefore, in according with the relevant IEC-61400 standards, it is development of clamping apparatus to test the composite blades in test platforms, and use engineering software (CAD/CAE) to support the design and experimental stage. In addition, it is effective to short the design cycle and reliability of simulated analysis. Finally, we are discussed the failure modes and test results of the SVAWT blades under different manufacturing processes to verify the proposed experimental setup methods and manufacture techniques of the SVAWT blades pass static test and fatigue test systems are performed, and established the fatigue life equation by fatigue theory can effectively prediction the life of SVAWT blades. The information of technology developed can be provided.

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Lennie, Matthew. "Development of the QFEM Solver : The Development of Modal Analysis Code for Wind Turbine Blades in QBLADE". Thesis, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-132154.

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The Wind Turbine industry continues to drive towards high market penetrationand profitability. In order to keep Wind Turbines in field for as long as possiblecomputational analysis tools are required. The open source tool QBlade[38] softwarewas extended to now contain routines to analyse the structural properties of WindTurbine blades. This was achieved using 2D integration methods and a Tapered Euler-Bernoulli beam element in order to find the mode shapes and 2D sectional properties.This was a key step towards integrating the National Renewable Energy LaboratoriesFAST package[32] which has the ability to analyse Aeroelastic Responses. The QFEMmodule performed well for the test cases including: hollow isotropic blade, rotatingbeam and tapered beam. Some improvements can be made to the torsion estimationof the 2D sections but this has no effect on the mode shapes required for the FASTsimulations.

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Jheng, Jhih-Kai, i 鄭至凱. "Design and Development of Lightweight Wind Turbine Blades based on External Force-bearing Cables and Modular Structure". Thesis, 2017. http://ndltd.ncl.edu.tw/handle/y786ud.

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