Готові списки джерел за темами / Turbine blade vibration

Добірка наукової літератури з теми "Turbine blade vibration"

Автор: Grafiati
Опубліковано: 14 березня 2023

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Статті в журналах з теми "Turbine blade vibration"

1

Loss, Theresa, and Alexander Bergmann. "Vibration-Based Fingerprint Algorithm for Structural Health Monitoring of Wind Turbine Blades." Applied Sciences 11, no. 9 (May 10, 2021): 4294. http://dx.doi.org/10.3390/app11094294.

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Анотація:
Monitoring the structural health of wind turbine blades is essential to increase energy capture and operational safety of turbines, and therewith enhance competitiveness of wind energy. With the current trends of designing blades ever longer, detailed knowledge of the vibrational characteristics at any point along the blade is desirable. In our approach, we monitor vibrations during operation of the turbine by wirelessly measuring accelerations on the outside of the blades. We propose an algorithm to extract so-called vibration-based fingerprints from those measurements, i.e., dominant vibrations such as eigenfrequencies and narrow-band noise. These fingerprints can then be used for subsequent analysis and visualisation, e.g., for comparing fingerprints across several sensor positions and for identifying vibrations as global or local properties. In this study, data were collected by sensors on two test turbines and fingerprints were successfully extracted for vibrations with both low and high operational variability. An analysis of sensors on the same blade indicates that fingerprints deviate for positions at large radial distance or at different blade sides and, hence, an evaluation with larger datasets of sensors at different positions is promising. In addition, the results show that distributed measurements on the blades are needed to gain a detailed understanding of blade vibrations and thereby reduce loads, increase energy harvesting and improve future blade design. In doing so, our method provides a tool for analysing vibrations with relation to environmental and operational variability in a comprehensive manner.
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2

Ando, Takashi. "Pulsation and Vibration Measurement on Stator Side for Turbocharger Turbine Blade Vibration Monitoring." International Journal of Turbomachinery, Propulsion and Power 5, no. 2 (May 25, 2020): 11. http://dx.doi.org/10.3390/ijtpp5020011.

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Анотація:
Mechanically robust turbine design with respect to blade vibration is challenging when dealing with nozzle-ring fouling and wear. Especially for engines operating with heavy fuel oil (HFO), the nozzle rings of the turbocharger turbines are prone to severe degradation in terms of contamination with unburned fuel deposits. This contamination will lead to an increased excitation of blade resonances in comparison to the nominal design. Due to the statistical character of contamination, long-term monitoring of blade vibration amplitudes would be beneficial. In the harsh environment of HFO operation, however, conventional blade vibration measurement techniques, such as those using strain gauges or blade tip timing, cannot work reliably for a long period. Thus, the objective of this research is to develop a method that enables the monitoring of turbine blades using pulsation or vibration sensors installed on the stator side. Almost a dozen turbines, both radial and axial, have been examined in order to determine a proper measurement chain/position and analytical method. Even though the challenges specific to the turbocharger turbine application—that high-frequency (up to 50 kHz) acoustic radiation from turbine blades has to be detected by a sensor on the stator side—were demanding, in the course of the investigations several clear examples of turbine blades engine-order resonance detection were gathered. Finally, the proposed method has been tested successfully in a power plant for over one year.
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3

Reinhardt, A. K., J. R. Kadambi, and R. D. Quinn. "Laser Vibrometry Measurements of Rotating Blade Vibrations." Journal of Engineering for Gas Turbines and Power 117, no. 3 (July 1, 1995): 484–88. http://dx.doi.org/10.1115/1.2814121.

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Анотація:
One of the most important design factors in modern turbomachinery is the vibration of turbomachinery blading. There is a need for developing an in-service, noncontacting, noninterfering method for the measurement and monitoring of gas turbine, jet engine, and steam turbine blade vibrations and stresses. Such a technique would also be useful for monitoring rotating helicopter blades. In the power generation industry, blade failures can result in millions of dollars of downtime. The measurement of blade vibrations and dynamic stresses is an important guide for preventive maintenance, which can be a major contributor to the availability of steam turbine, gas turbine, and helicopter operations. An experiment is designed to verify the feasibility of such a vibration monitoring system using the reference beam on-axis laser-Doppler technique. The experimental setup consists of two flat, cantilever blades mounted on a hub attached to the shaft of a dc motor. The motor rests on a linear bearing permitting motion only in the direction of the motor shaft. The motor and blade assembly is then excited via an electrodynamic shaker at the first natural frequency of the blades. The resulting blade vibration is then detected using a laser vibrometer. The vibration frequencies and amplitudes of the two rotating blades are successfully measured.
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4

Gantasala, Sudhakar, Narges Tabatabaei, Michel Cervantes, and Jan-Olov Aidanpää. "Numerical Investigation of the Aeroelastic Behavior of a Wind Turbine with Iced Blades." Energies 12, no. 12 (June 24, 2019): 2422. http://dx.doi.org/10.3390/en12122422.

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Анотація:
Wind turbines installed in cold-climate regions are prone to the risks of ice accumulation which affects their aeroelastic behavior. The studies carried out on this topic so far considered icing in a few sections of the blade, mostly located in the outer part of the blade, and their influence on the loads and power production of the turbine are only analyzed. The knowledge about the influence of icing in different locations of the blade and asymmetrical icing of the blades on loads, power, and vibration behavior of the turbine is still not matured. To improve this knowledge, multiple simulation cases are needed to run with different ice accumulations on the blade considering structural and aerodynamic property changes due to ice. Such simulations can be easily run by automating the ice shape creation on aerofoil sections and two-dimensional (2-D) Computational Fluid Dynamics (CFD) analysis of those sections. The current work proposes such methodology and it is illustrated on the National Renewable Energy Laboratory (NREL) 5 MW baseline wind turbine model. The influence of symmetrical icing in different locations of the blade and asymmetrical icing of the blade assembly is analyzed on the turbine’s dynamic behavior using the aeroelastic computer-aided engineering tool FAST. The outer third of the blade produces about 50% of the turbine’s total power and severe icing in this part of the blade reduces power output and aeroelastic damping of the blade’s flapwise vibration modes. The increase in blade mass due to ice reduces its natural frequencies which can be extracted from the vibration responses of the turbine operating under turbulent wind conditions. Symmetrical icing of the blades reduces loads acting on the turbine components, whereas asymmetrical icing of the blades induces loads and vibrations in the tower, hub, and nacelle assembly at a frequency synchronous to rotational speed of the turbine.
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5

Biglari, Hamed, and Vahid Fakhari. "Edgewise vibration reduction of small size wind turbine blades using shunt damping." Journal of Vibration and Control 26, no. 3-4 (September 24, 2019): 186–99. http://dx.doi.org/10.1177/1077546319877706.

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Анотація:
Edgewise vibration in wind turbine blades is one of the important factors that results in reducing the performance of wind turbines. Therefore, control or reduction of the mentioned vibrations can be of great help in increasing the efficiency of wind turbines. In this paper, the shunt damping method is proposed to reduce the edgewise blade vibration of horizontal axis wind turbines. For this purpose, partial differential equations governing dynamics of the system are derived using the Lagrange method. These equations are completely nonlinear and linearization is not performed to avoid possible errors in the analysis. In order to evaluate the effectiveness of the proposed shunt damping method in vibration reduction of the wind turbine blade, obtained results by applying shunt damping method are compared with corresponding results obtained by employing a conventional method known as a tuned mass damper (TMD). For better comparison, by considering proper cost functions, the shunt damper and TMD parameters are optimized using a genetic algorithm. Finally, the effectiveness of optimized shunt damper in vibration reduction of the blade is compared with optimized TMD by presenting simulation results.
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6

Zhang, Qinglei, Haoyang Wang, Jiyun Qin, and Jianguo Duan. "Study on the collision dynamics of integral shroud blade for high-pressure turbine in different integral shroud clearance distance." Noise & Vibration Worldwide 52, no. 7-8 (March 12, 2021): 200–211. http://dx.doi.org/10.1177/0957456521999874.

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Анотація:
In steam turbine, turbine blades are prone to vibrate during operation, resulting in steam turbine accidents. The most common method for reducing the vibration of steam turbine blades is to design an integral shroud for blade which is termed as integral shroud blade. Most previous studies simplified straight integral blades into cantilever beam and used harmonic response analysis method to simulate the vibration response of blades. This method is suitable for simulating straight blade vibration under harmonic force conditions. For twisted blades, accurate results are hard to acquire and the specific collision process cannot be simulated. In order to observe the collision process on a microscopic scale and explore its collision damping mechanism, this study evaluated the collision process of twisted blades with different integral shroud clearance distance based on LS-DYNA software. The collision process for a two-blade system and a three-blade system with integral shroud clearance distance from 0.1 mm to 0.5 mm has been simulated. The results indicated that integral shroud clearance distance have opposite vibration damping effect when the blade under the condition of forced vibration and free vibration. For the two-blade system, the optimal integral shroud clearance distance is 0.4 mm for forced vibration condition and 0.1 mm for free vibration condition. For the three-blade system, the optimal integral shroud clearance distance is 0.1 mm for forced vibration condition and 0.5 mm for free vibration condition.
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7

Rzadkowski, Romuald, Leszek Kubitz, Michał Maziarz, Pawel Troka, Krzysztof Dominiczak, and Ryszard Szczepanik. "Tip-Timing Measurements and Numerical Analysis of Last-Stage Steam Turbine Mistuned Bladed Disc During Run-Down." Journal of Vibration Engineering & Technologies 8, no. 3 (October 25, 2019): 409–15. http://dx.doi.org/10.1007/s42417-019-00185-2.

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Анотація:
Abstract Background This paper presents the experimental and numerical studies of last-stage low-pressure (LP) mistuned steam turbine bladed discs during run-down. Methods The natural frequencies and mode shapes of the turbine bladed disc were calculated using an FE model. The influence of the shaft on the modal properties, such as natural frequencies and mode shapes, was considered. The tip-timing method was used to find the mistuned bladed disc modes and frequencies. Conclusions The experimental results from the tip-timing analysis show that the mistuning in combination with shaft coupling suppresses pure nodal diameter type blade vibrations associated with the fundamental mode shape of a cantilevered blade. Vibration modes emerge when even a single blade is vibrating due to the well-known mode localization caused by mistuning. The numerical results confirm this.
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8

Liska, Jindrich, Vojtech Vasicek, and Jan Jakl. "A Novel Method of Impeller Blade Monitoring Using Shaft Vibration Signal Processing." Sensors 22, no. 13 (June 29, 2022): 4932. http://dx.doi.org/10.3390/s22134932.

Повний текст джерела
Анотація:
The monitoring of impeller blade vibrations is an important task in the diagnosis of turbomachinery, especially in terms of steam turbines. Early detection of potential faults is the key to avoid the risk of turbine unexpected outages and to minimize profit loss. One of the ways to achieve this is long-term monitoring. However, existing monitoring systems for impeller blade long-term monitoring are quite expensive and also require special sensors to be installed. It is even common that the impeller blades are not monitored at all. In recent years, the authors of this paper developed a new method of impeller blade monitoring that is based on relative shaft vibration signal measurement and analysis. In this case, sensors that are already standardly installed in the bearing pedestal are used. This is a significant change in the accessibility of blade monitoring for a steam turbine operator in terms of expenditures. This article describes the developed algorithm for the relative shaft vibration signal analysis that is designed to run in a long-term perspective as a part of a remote monitoring system to track the natural blade frequency and its amplitude automatically.
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9

Rani, Pooja, and Atul Kumar Agrawal. "Natural Frequency Evaluation of Low-Pressure Stage Blade of a 210 MW Steam Turbine." IOP Conference Series: Materials Science and Engineering 1248, no. 1 (July 1, 2022): 012032. http://dx.doi.org/10.1088/1757-899x/1248/1/012032.

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Анотація:
Abstract Steam turbines rely heavily on the performance and reliability of their rotor blades. When a steam turbine blade fails, it can pose a risk to workers' life, need expensive repairs, and cause income losses. The failure mechanism differs from case to case and is typically quite complex. The last stage turbine blades are very long and rotate at high speed. In extreme dynamic loads, these big blades are the most susceptible to failure. So, the dynamic behaviour of the last stage steam turbine blade is of great importance and analysed by numerical simulation in this work. Mode shapes at natural frequencies of the blade at stationary condition and at different speeds of rotation are determined. A Campbell diagram is used to forecast the expected operational conditions that may result in blade resonant vibration.
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10

Rogge, Timo, Ricarda Berger, Linus Pohle, Raimund Rolfes, and Jörg Wallaschek. "Efficient structural analysis of gas turbine blades." Aircraft Engineering and Aerospace Technology 90, no. 9 (November 14, 2018): 1305–16. http://dx.doi.org/10.1108/aeat-05-2016-0085.

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Анотація:
Purpose The purpose of this study a fast procedure for the structural analysis of gas turbine blades in aircraft engines. In this connection, investigations on the behavior of gas turbine blades concentrate on the analysis and evaluation of starting dynamics and fatigue strength. Besides, the influence of structural mistuning on the vibration characteristics of the single blade is analyzed and discussed. Design/methodology/approach A basic computation cycle is generated from a flight profile to describe the operating history of the gas turbine blade properly. Within an approximation approach for high-frequency vibrations, maximum vibration amplitudes are computed by superposition of stationary frequency responses by means of weighting functions. In addition, a two-way coupling approach determines the influence of structural mistuning on the vibration of a single blade. Fatigue strength of gas turbine blades is analyzed with a semi-analytical approach. The progressive damage analysis is based on MINER’s damage accumulation assuming a quasi-stable behavior of the structure. Findings The application to a gas turbine blade shows the computational capabilities of the approach presented. Structural characteristics are obtained by robust and stable computations using a detailed finite element model considering different load conditions. A high quality of results is realized while reducing the numerical costs significantly. Research limitations/implications The method used for analyzing the starting dynamics is based on the assumption of a quasi-static state. For structures with a sufficiently high stiffness, such as the gas turbine blades in the present work, this procedure is justified. The fatigue damage approach relies on the existence of a quasi-stable cyclic stress condition, which in general occurs for isotropic materials, as is the case for gas turbine blades. Practical implications Owing to the use of efficient analysis methods, a fast evaluation of the gas turbine blade within a stochastic analysis is feasible. Originality/value The fast numerical methods and the use of the full finite element model enable performing a structural analysis of any blade structure with a high quality of results.
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Більше джерел

Дисертації з теми "Turbine blade vibration"

1

Esu, Ozak O. "Vibration-based condition monitoring of wind turbine blades." Thesis, Loughborough University, 2016. https://dspace.lboro.ac.uk/2134/21679.

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Анотація:
Significant advances in wind turbine technology have increased the need for maintenance through condition monitoring. Indeed condition monitoring techniques exist and are deployed on wind turbines across Europe and America but are limited in scope. The sensors and monitoring devices used can be very expensive to deploy, further increasing costs within the wind industry. The work outlined in this thesis primarily investigates potential low-cost alternatives in the laboratory environment using vibration-based and modal testing techniques that could be used to monitor the condition of wind turbine blades. The main contributions of this thesis are: (1) the review of vibration-based condition monitoring for changing natural frequency identification; (2) the application of low-cost piezoelectric sounders with proof mass for sensing and measuring vibrations which provide information on structural health; (3) the application of low-cost miniature Micro-Electro-Mechanical Systems (MEMS) accelerometers for detecting and measuring defects in micro wind turbine blades in laboratory experiments; (4) development of an in-service calibration technique for arbitrarily positioned MEMS accelerometers on a medium-sized wind turbine blade. This allowed for easier aligning of coordinate systems and setting the accelerometer calibration values using samples taken over a period of time; (5) laboratory validation of low-cost modal analysis techniques on a medium-sized wind turbine blade; (6) mimicked ice-loading and laboratory measurement of vibration characteristics using MEMS accelerometers on a real wind turbine blade and (7) conceptualisation and systems design of a novel embedded monitoring system that can be installed at manufacture, is self-powered, has signal processing capability and can operate remotely. By applying the conclusions of this work, which demonstrates that low-cost consumer electronics specifically MEMS accelerometers can measure the vibration characteristics of wind turbine blades, the implementation and deployment of these devices can contribute towards reducing the rising costs of condition monitoring within the wind industry.
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2

Kelen, Peter. "A finite element analysis of the vibration characteristics of rotating turbine blade assemblies." Thesis, University of Surrey, 1985. http://epubs.surrey.ac.uk/2098/.

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3

Flood, Robert C. "Vibrations of an isolated wind turbine blade using the finite element method." Thesis, Virginia Polytechnic Institute and State University, 1986. http://hdl.handle.net/10919/91089.

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Анотація:
The finite element method is applied to an isolated and twisted wind turbine blade which is rotating in a vertical plane to determine its structural dynamic characteristics. The equations of motion are formulated for a rotating beam with flap and lead-lag degrees of freedom subjected to nonsymmetric bending. Using a variational approach, a blade finite clement is developed from these equations of motion. Additionally, expressions are formulated for the elastic strain energy and kinetic energy of a rotating wind turbine blade. Lagrange's equation is applied to these energy expressions and an isoparametric finite element based on three dimensional elasticity and quadratic interpolation functions is developed. Both sets of finite element equations are implemented in a general purpose computer program to solve the structural dynamics eigenvalue problem and results compare favorably with published data for the cases of a nontwisted cantilevered beam both at rest and while rotating. A blade finite element model of a 10KW horizontal axis wind turbine blade is presented and its lowest modes of vibration are calculated for the cases of the blade at rest and in operation at rotor speeds up to 250 RPM.
M.S.
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4

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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5

Tartibu, Kwanda. "A simplified analysis of the vibration of variable length blade as might be used in wind turbine systems." Thesis, Cape Peninsula University of Technology, 2008. http://hdl.handle.net/20.500.11838/1244.

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Анотація:
Vibration is an inherent phenomenon in dynamic mechanical systems. The work undertaken in this thesis is to identify natural frequencies of a variable length blade. Therefore designers can ensure that natural frequencies will not be close to the frequency (or integer multiples) of the main excitation forces in order to avoid resonance. For a wind turbine blade, the frequency range between 0.5 Hz and 30 Hz is relevant. The turbine blade is approximated by a cantilever, therefore, it is fully constrained where attached to a turbine shaft/hub. Flap-wise, edge-wise and torsional natural frequencies are calculated. The MATLAB program “BEAMANALYSIS.m” has been developed for the finite element analysis of a one dimensional model of the beam. Similarly, a three dimensional model of the beam has been developed in a finite element program Unigraphics NX5. The results found using the MATLAB program are compared with those found with NX5. Satisfactory agreement between the results is found for frequencies up to almost 500 Hz. Additionally, the frequencies one might expect in an experiment are identified. Experimental modal analysis has been performed on a uniform and stepped beam made of mild steel to extract the first five flap-wise natural frequencies. The results found have been compared to numerical results and the exact solution of an Euler-Bernoulli beam. Concurrence is found for the frequency range of interest. Although, some discrepancies exist at higher frequencies (above 500 Hz), finite element analysis proves to be reliable for calculating natural frequencies. Finally, the fixed portion and moveable portion of the variable length blade are approximated respectively by a hollow and a solid beam which can be slid in and out. Ten different configurations of the variable length blade, representing ten different positions of the moveable portion are investigated. A MATLAB program named VARIBLADEANALYSIS.m was developed to predict natural frequencies. Similarly three dimensional models of the variable length blade have been developed in the finite element program Unigraphics NX5.
This work was supported by the Research office of CPUT.
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6

Zdunek, Agnieszka Izabela. "Prediction of natural frequencies of turbine blades for turbocharger application : an investigation of the finite element method, mathematical modelling and frequency survey methods applied to turbocharger blade vibration in order to predict natural frequencies of turbocharger blades." Thesis, University of Bradford, 2014. http://hdl.handle.net/10454/7328.

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Анотація:
Methods of determining natural frequencies of the D76D88, B76D88, A86E93, C86G90, C86L90 and C125L89 turbine wheel designs for various environmental conditions were investigated by application of Finite Element Analysis and beam theory. Modelling and simulation methods were developed ; the first method composed of 15 finite element simulations ; the second composed of 15 finite element simulations and a set of experimental frequency survey results; the third composed of 5 simulations , an incorporated mathematical model and a set of experimental frequency survey results. Each of these methods was designed to allow prediction of resonant frequency changes across a range of exhaust gas temperature and shaft rotational speed. For the new modelling and simulation methods, an analysis template and a plotting tool were developed using Microsoft Excel and MATLAB software. A graph showing a frequency-temperature-speed variations and a Campbell Diagram that incorporates material stiffening and softening effects across a range of rotational speeds was designed, and applied to the D76D88, B76D88, A86E93, C86G90, C86L90 and C125L89 turbine wheel designs. New design methodologies for turbine wheels were formulated and validated, showing a good agreement with a range of data points from frequency survey, strain-gauge telemetry and laser tip-timing test results. The results from the new design method were compared with existing single compensation factor methodology, and showed a great improvement in accuracy of prediction of modal vibration. A new nomenclature for the mode shapes of a turbocharger’s blade was proposed, designed and demonstrated to allow direct identification of associated mode shape. It is concluded that Finite Element Analysis combined with the frequency survey is capable of predicting changes in turbine natural frequencies and, when incorporated into the existing turbine design methodology, resulted in a major improvement in the accuracy of the predictions of vibration frequency.
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7

Van, Dyke Jason. "Modeling Behaviour of Damaged Turbine Blades for Engine Health Diagnostics and Prognostics." Thèse, Université d'Ottawa / University of Ottawa, 2011. http://hdl.handle.net/10393/20312.

Повний текст джерела
Анотація:
The reliability of modern gas turbine engines is largely due to careful damage tolerant design a method of structural design based on the assumption that flaws (cracks) exist in any structure and will continue to grow with usage. With proper monitoring, largely in the form of periodic inspections at conservative intervals reliability and safety is maintained. These methods while reliable can lead to the early retirement of some components and unforeseen failure if design assumptions fail to reflect reality. With improvements to sensor and computing technology there is a growing interest in a system that could continuously monitor the health of structural aircraft as well as forecast future damage accumulation in real-time. Through the use of two-dimensional and three-dimensional numerical modeling the initial goals and findings for this continued work include: (a) establishing measurable parameters directly linked to the health of the blade and (b) the feasibility of detecting accumulated damage to the structural material and thermal barrier coating as well as the onset of damage causing structural failure.
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8

Tournu, Erik. "Modélisation stochastique du comportement dynamique non linéaire d'un ailetage de turbine : application à une poutre avec contact oblique." Vandoeuvre-les-Nancy, INPL, 1996. http://www.theses.fr/1996INPL118N.

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Анотація:
Des méthodes d'analyse en dynamique stochastique sont étudiées pour une maquette avec contact oblique. Elles ont pour objet de déterminer les caractéristiques statistiques de la réponse de la structure non linéaire soumise à des sollicitations aléatoires. La maquette représente une ailette avec ses ailerons qui sont en contact avec les ailerons voisins. Cette maquette est modélisée par la théorie des poutres d'Euler-Bernoulli pour l'ailette et par le modèle curvilinéaire de Bouc-Wen pour la non-linéarité de contact. Les résultats de ce modèle de comportement sont comparés avec succès à ceux d'une maquette de laboratoire qui concrétise la poutre avec les contacts obliques, sollicitées par des processus aléatoires. Les caractéristiques du processus de réponse du modèle de comportement soumis à des sollicitations aléatoires sont déterminées par la méthode de Monte-Carlo basée sur la simulation numérique des processus à partir des densités spectrales et par la méthode de linéarisation stochastique gaussienne basée sur l'équation de Lyapunov. Les résultats de ces deux méthodes concordent et ont mis en évidence trois domaines de comportement: pour les faibles excitations, il y a adhérence, pour les excitations moyennes, il y a glissement avec effort tangentiel limité constant et pour les excitations élevées, il y a glissement avec effort tangentiel limité croissant
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9

Horák, Petr. "Energetická bilance tvarů kmitání lopatky poslední řady parní turbíny." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2012. http://www.nusl.cz/ntk/nusl-230409.

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Анотація:
Created methodology for calculating the potential deformation energy parts is described in this thesis. Calculation method uses the outputs of modal analysis, which is performed using computational modelling. The potential deformation energy parts are calculated for three cases. Two benchmark problems and one case of blade model. Blade geometry is received by 3D scanning and reconstruction of given specimen. Results of the potential deformation energy parts calculations are analyzed and conclusions are formulated.
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10

Cantoni, Lorenzo. "Load Control Aerodynamics in Offshore Wind Turbines." Thesis, KTH, Kraft- och värmeteknologi, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-291417.

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Анотація:
Due to the increase of rotor size in horizontal axis wind turbine (HAWT) during the past 25 years in order to achieve higher power output, all wind turbine components and blades in particular, have to withstand higher structural loads. This upscalingproblem could be solved by applying technologies capable of reducing aerodynamic loads the rotor has to withstand, either with passive or active control solutions. These control devices and techniques can reduce the fatigue load upon the blades up to 40% and therefore less maintenance is needed, resulting in an important money savings for the wind farm manager. This project consists in a study of load control techniques for offshore wind turbines from an aerodynamic and aeroelastic point ofview, with the aim to assess a cost effective, robust and reliable solution which could operate maintenance free in quite hostile environments. The first part of this study involves 2D and 3D aerodynamic and aeroelastic simulations to validate the computational model with experimental data and to analyze the interaction between the fluid and the structure. The second part of this study is an assessment of the unsteady aerodynamic loads produced by a wind gust over the blades and to verify how a trailing edge flap would influence the aerodynamic control parameters for the selected wind turbine blade.
På grund av ökningen av rotorstorleken hos horisontella vindturbiner (HAWT) under de senaste 25 åren, en design som har uppstod för att uppnå högre effekt, måste alla vindkraftkomponenter och blad stå emot högre strukturella belastningar. Detta uppskalningsproblem kan lösas genom att använda metoder som kan minska aerodynamiska belastningar som rotorn måste tåla, antingen med passiva eller aktiva styrlösningar. Dessa kontrollanordningar och tekniker kan minska utmattningsbelastningen på bladen med upp till 40 % och därför behövs mindre underhåll, vilket resulterar i viktiga besparingar för vindkraftsägaren. Detta projekt består av en studie av lastkontrolltekniker för havsbaserade vindkraftverk ur en aerodynamisk och aeroelastisk synvinkel, i syfte att bedöma en kostnadseffektiv, robust och pålitlig lösning som kan fungera underhållsfri i tuffa miljöer. Den första delen av denna studie involverar 2D- och 3D-aerodynamiska och aeroelastiska simuleringar för att validera beräkningsmodellen med experimentella data och för att analysera interaktionen mellan fluiden och strukturen. Den andra delen av denna studie är en bedömning av de ojämna aerodynamiska belastningarna som produceras av ett vindkast över bladen och för att verifiera hur en bakkantklaff skulle påverka de aerodynamiska styrparametrarna för det valda vindturbinbladet.
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Книги з теми "Turbine blade vibration"

1

Martinez-Sanchez, Manuel. Turbine blade-tip clearance excitation forces: Final report on Contract number NAS8-35018. Cambridge, Mass: Massachusetts Institute of Technology, 1985.

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2

Martinez-Sanchez, Manuel. Turbine blade-tip clearance excitation forces: Final report on Contract number NAS8-35018. Cambridge, Mass: Massachusetts Institute of Technology, 1985.

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3

M, Greitzer Edward, George C. Marshall Space Flight Center., and Massachusetts Institute of Technology, eds. Turbine blade-tip clearance excitation forces: Final report on Contract number NAS8-35018. Cambridge, Mass: Massachusetts Institute of Technology, 1985.

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4

M, Greitzer Edward, George C. Marshall Space Flight Center, and Massachusetts Institute of Technology, eds. Turbine blade-tip clearance excitation forces: Final report on Contract number NAS8-35018. Cambridge, Mass: Massachusetts Institute of Technology, 1985.

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5

R, Little Ronald, and United States. National Aeronautics and Space Administration, eds. Application of a personal computer for the uncoupled vibration analysis of wind turbine blade and counterweight assemblies. [Washington, DC: National Aeronautics and Space Administration, 1985.

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6

V, Nagpal, Chamis C. C, and United States. National Aeronautics and Space Administration., eds. Probabilistic analysis of bladed turbine disks and the effect of mistuning. [Washington, D.C: National Aeronautics and Space Administration, 1990.

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7

1959-, Pierre Christophe, and United States. National Aeronautics and Space Administration., eds. Stochastic sensitivity measure for mistuned high-performance turbines. [Washington, DC]: National Aeronautics and Space Administration, 1992.

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8

Center, Lewis Research, ed. Effects of mistuning and matrix structure on the topology of frequency response curves. Cleveland, Ohio: Lewis Research Center, 1989.

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9

Afolabi, Dare. Effects of mistuning and matrix structure on the topology of frequency response curves. Cleveland, Ohio: Lewis Research Center, 1989.

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10

Brown, K. W. Structural Tailoring of Advanced Turboprops (STAT): Programmer's manual. [Washington, DC]: National Aeronautics and Space Administration, 1989.

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Частини книг з теми "Turbine blade vibration"

1

Devi Priya, T., Sunil Kumar, Devendra Pratap, S. Shylaja, T. N. Satish, and A. N. Vishwanatha Rao. "Rotor Blade Vibration Measurement on Aero Gas Turbine Engines." In Proceedings of the National Aerospace Propulsion Conference, 263–73. Singapore: Springer Singapore, 2020. http://dx.doi.org/10.1007/978-981-15-5039-3_15.

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2

Pei, Wei, Dongmei Zhang, and Jizhong Zhang. "Vibration Property Analysis of Turbocharger Turbine Blade Under Different Loads." In Fluid Machinery and Fluid Mechanics, 242–45. Berlin, Heidelberg: Springer Berlin Heidelberg, 2009. http://dx.doi.org/10.1007/978-3-540-89749-1_35.

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3

Dana, S. R., and D. E. Adams. "Operational Damage Detection of Turbine Rotors using Integrated Blade Sensors." In Rotating Machinery, Structural Health Monitoring, Shock and Vibration, Volume 5, 277–86. New York, NY: Springer New York, 2011. http://dx.doi.org/10.1007/978-1-4419-9428-8_22.

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4

Deines, Krystal, Timothy Marinone, Ryan Schultz, Kevin Farinholt, and Gyuhae Park. "Modal Analysis and SHM Investigation of CX-100 Wind Turbine Blade." In Rotating Machinery, Structural Health Monitoring, Shock and Vibration, Volume 5, 413–38. New York, NY: Springer New York, 2011. http://dx.doi.org/10.1007/978-1-4419-9428-8_36.

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5

Hashemi, Ali, and Jinwoo Jang. "Smart Active Vibration Control System of a Wind Turbine Blade Using Piezoelectric Material." In Conference Proceedings of the Society for Experimental Mechanics Series, 1–15. Cham: Springer International Publishing, 2022. http://dx.doi.org/10.1007/978-3-031-05449-5_1.

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6

Zhao, Weiqiang, Yongxian Liu, Mowu Lu, and Qingjun Guo. "Vibration Analysis of a Certain Type of Aero-engine Turbine Blade Based on UG." In Informatics in Control, Automation and Robotics, 377–82. Berlin, Heidelberg: Springer Berlin Heidelberg, 2011. http://dx.doi.org/10.1007/978-3-642-25992-0_53.

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7

Panagiotopoulos, A. I., D. Tcherniak, and S. D. Fassois. "Damage Detection on an Operating Wind Turbine Blade via a Single Vibration Sensor: A Feasibility Study." In Lecture Notes in Civil Engineering, 405–14. Cham: Springer International Publishing, 2021. http://dx.doi.org/10.1007/978-3-030-64908-1_38.

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8

Panagiotopoulos, A. I., D. Tcherniak, and S. D. Fassois. "Damage Detection on an Operating Wind Turbine Blade via a Single Vibration Sensor: A Feasibility Study." In Lecture Notes in Civil Engineering, 405–14. Cham: Springer International Publishing, 2021. http://dx.doi.org/10.1007/978-3-030-64908-1_38.

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9

Asl, Mohamad Eydani, Christopher Niezrecki, James Sherwood, and Peter Avitabile. "Design of Scaled-Down Composite I-Beams for Dynamic Characterization in Subcomponent Testing of a Wind Turbine Blade." In Shock & Vibration, Aircraft/Aerospace, Energy Harvesting, Acoustics & Optics, Volume 9, 197–209. Cham: Springer International Publishing, 2016. http://dx.doi.org/10.1007/978-3-319-30087-0_18.

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10

Ozbek, Muammer, and Daniel J. Rixen. "3D Blade Vibration Measurements on an 80 m Diameter Wind Turbine by Using Non-contact Remote Measurement Systems." In Springer Proceedings in Physics, 273–78. Cham: Springer International Publishing, 2014. http://dx.doi.org/10.1007/978-3-319-05521-3_35.

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Тези доповідей конференцій з теми "Turbine blade vibration"

1

Tamai, Ryoji, Ryozo Tanaka, Yoshichika Sato, Karsten Kusterer, Gang Lin, Martin Kemper, and Lars Panning-von Scheidt. "Vibration Analysis of Shrouded Turbine Blades for a 30 MW Gas Turbine." In ASME 2013 Turbine Blade Tip Symposium. American Society of Mechanical Engineers, 2013. http://dx.doi.org/10.1115/tbts2013-2014.

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Анотація:
Turbine blades are subjected to high static and dynamic loads. In order to reduce the vibration amplitude means of friction damping devices have been developed, e.g. damping wires, interblade friction dampers and shrouds. This paper presents both numerical and experimental results for investigating the dynamical behavior of shrouded turbine blades. The studies are focused on the lowest family of the bladed disk. The aspect of experimental studies, the effect of the shroud contact force on the resonance frequency of the blade was examined by using the simplified blade test stand. Based on the result of the simplified blade studies, the shroud contact force of the real blade was determined in order to stabilize the resonance frequencies of the bladed disk system. The resonance frequencies and mode shapes of the real bladed disk assembly were measured in no rotation and room temperature condition. Finally, the dynamic strains were measured in the actual engine operations by using a telemetry system. The aspect of analytical studies, a non-linear vibration analysis code named DATES was applied to predict vibration behavior of a shrouded blade model which includes contact friction surfaces. The DATES code is a forced response analysis code that employs a 3-dimensional friction contact model. The Harmonic Balance Method (HBM) is applied to solve resulting nonlinear equations of motion in frequency domain. The simulated results show a good agreement with the experimental results.
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2

Kawashima, T., H. Iinuma, T. Wakatsuki, and N. Minagawa. "Turbine Blade Vibration Monitoring System." In ASME 1992 International Gas Turbine and Aeroengine Congress and Exposition. American Society of Mechanical Engineers, 1992. http://dx.doi.org/10.1115/92-gt-159.

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This paper describes a development and an evaluation of an optical blade vibration monitoring system applicable to gas turbine engine high pressure turbine blading. The system uses high intensity He-Ne lasers, optical fibers and associated electronics, and can monitor rotor blade vibration under engine running conditions. With a combined water and air probe cooling system, it can be used for monitoring turbine blade vibration at 1300 degree C range gas temperature. The system was applied to actual gas turbine engines and has demonstrated it’s effectiveness as a useful tool for gas turbine blade vibration evaluation.
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3

Bachschmid, Nicolò, Emanuel Pesatori, Simone Bistolfi, and Massimiliano Sanvito. "Building Up Suitable Contact Forces in Integrally Shrouded Blade Rows for Reducing Vibration Amplitudes." In ASME 2013 Turbine Blade Tip Symposium. American Society of Mechanical Engineers, 2013. http://dx.doi.org/10.1115/tbts2013-2005.

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The beneficial effects of the contact between shrouds are described extensively in recent literature: natural blade frequencies are increased and additional damping is available. Different models are proposed for analyzing its linear and nonlinear behavior, selection of optimum contact forces are proposed for reducing vibration amplitudes to a minimum. Results from different non linear analyses that use different models all based generally on a reduced modal model of the blade row and on the harmonic balance approach for modeling the non linear contact forces, are sometimes contradictory: some claim e.g. that increasing excitation amplitude leads to a reduction of the dynamic magnification factor (due to friction damping increase) some other claim the opposite. The contribution to this topic of the present paper is the analysis of the effect of a “contact shim” which can be inserted in a cavity between adjacent shrouds. The shim generates suitable contact forces between the shrouds of the blades of a row, which without shim would vibrate as free standing blades.
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4

Techy, Laszlo, Brynn De Gooyer, Andy von Flotow, Peter Tappert, Shaju John, David Losh, and Benjamin Lewit. "Turbine Blade Crack Detection Using Blade Vibration Monitoring: Field Study From an Operating Steam Turbine." In ASME Turbo Expo 2022: Turbomachinery Technical Conference and Exposition. American Society of Mechanical Engineers, 2022. http://dx.doi.org/10.1115/gt2022-79829.

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Abstract Blade Vibration Monitoring techniques were employed at an operating power-generating steam turbine to measure and analyze blade vibrations and monitor turbine blade health. The blade row of interest was the last row of freestanding low-pressure turbine blades that had a known history of blade root cracking. The monitoring instruments were blade tip timing probes that were permanently fixed to the casing, and recorded time of arrival of each passing blade. During normal operation of the steam turbine, a group of blades was experiencing high vibrations that eventually led to crack initiation and subsequent crack growth in one blade. The blade natural frequency changed as a consequence, which was detectable in the blade health trending data, and triggered an advisory for machine shutdown for unscheduled maintenance in order to inspect the blades. The inspection consisted of Phased Array Ultrasonic Testing for in-situ evaluation, which confirmed the crack in the same blade where the monitoring system indicated. The blade was removed, and Fluorescent Magnetic Particle Inspection also confirmed the crack. The Blade Vibration Monitoring system not only identified the root cause of cracking, but possibly prevented turbine blade failure.
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5

Haupt, U., K. Bammert, and M. Rautenberg. "Blade Vibration on Centrifugal Compressors: Blade Response to Different Excitation Conditions." In ASME 1985 International Gas Turbine Conference and Exhibit. American Society of Mechanical Engineers, 1985. http://dx.doi.org/10.1115/85-gt-93.

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Results and analysis of blade vibration measurements on a high pressure ratio / high mass flow centrifugal compressor made with strain gages and using multichannel telemetry are described for compressors with 3 different types of vaned diffusers. Considerable high frequency blade excitation and vibration of the shallow region near the impeller outlet were observed. Initial progress to predict this dangerous excitation caused by the diffuser vanes was made with the help of FE computations using a simplified element system consisting of the vibrating zones of a 90° sector of the impeller. Satisfactory agreement with measured vibration data was achieved. The influence of rotating stall on blade excitation was investigated using different types of vaned diffusers leading to different numbers of rotating stall zones and variations in the rotational speed of the cells. Blade vibration intensity due to surge in conjunction with variations of the diffuser is also considered. Holographic interferometry was successfully applied to blade vibration measurements on compressors in operation. The investigation was aimed at studying the occurrence of blade modes and the vibratory behavior of the different blades near the interesting inlet zone. The occurrence of different constellations of blade modes at a resonance point and at an operating point far from resonance was demonstrated.
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6

Wagner, L. F., and J. H. Griffin. "Blade Vibration With Nonlinear Tip Constraint: Model Development." In ASME 1989 International Gas Turbine and Aeroengine Congress and Exposition. American Society of Mechanical Engineers, 1989. http://dx.doi.org/10.1115/89-gt-293.

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Turbine blades having integrally-machined tip shrouds, with associated gaps between adjacent shrouds, often exhibit unusual vibratory responses with significant differences between the amplitudes and frequencies of individual blades on the same stage. These differences result from unavoidable variations in the shroud gaps causing, for large enough excitation, nonlinear constraint at the blade tips which varies from blade to blade. This study shows that the blade stresses cannot be adequately represented by the type of single degree-of-freedom models that are often used for dynamic impact studies, but require the participation of higher frequency beam-type modes. The extension of the resulting beam model to multi-degree-of-freedom systems will allow the study of the “gap mistuning” phenomenon for practical bladed disks.
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7

Hoskoti, Lokanna, Ajay Misra, and Mahesh Manchakattil Sucheendran. "Vortex Induced Vibration of a Rotating Blade." In ASME 2017 Gas Turbine India Conference. American Society of Mechanical Engineers, 2017. http://dx.doi.org/10.1115/gtindia2017-4709.

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The vortex-induced vibration (VIV) of a rotating blade is studied in this paper. Euler-Bernoulli beam equation and the nonlinear oscillator satisfying Van der Pol equation are used to model the rotating blade and vortex shedding, respectively. While the fluctuating lift due to vortex shedding acts on the blade and the blade is coupled with fluid through a linear inertial coupling, resulting in a fluid-structure interaction problem. The coupled equations are discretized by using modes which satisfy the Eigenvalue problem. The work attempts to understand the instabilities associated with the frequency lock-in phenomenon. The method of multiscale is used to obtain the frequency response equation and frequency bifurcation diagrams of the coupled system. They are obtained for the primary (1:1) resonance for different values of the coupling parameter. The stability of the solution is presented by examining the nature of the Eigenvalues of the Jacobian matrix.
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8

Lerche, Andrew H., J. Jeffrey Moore, and Timothy C. Allison. "Experimental Study of Blade Vibration in Centrifugal Compressors." In ASME 2011 Turbo Expo: Turbine Technical Conference and Exposition. ASMEDC, 2011. http://dx.doi.org/10.1115/gt2011-45928.

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Blade vibration in turbomachinery is a common problem that can lead to blade failure by high cycle fatigue. Although much research has been performed on axial flow turbomachinery, little has been published for radial flow machines such as centrifugal compressors and radial inflow turbines. This work develops a test rig that measures the resonant vibration of centrifugal compressor blades. The blade vibrations are caused by the wakes coming from the inlet guide vanes. These vibrations are measured using blade mounted strain gauges during a rotating test. The total damping of the blade response from the rotating test is compared to the damping from the modal testing performed on the impeller. The mode shapes of the response and possible effects of mistuning are also discussed. The results show that mistuning can affect the phase cancellation which one would expect to see on a system with perfect cyclic symmetry.
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9

Kubin, Zdenek, Vaclav Polreich, Vaclav Cerny, Petra Babkova, and Lubos Prchlik. "Damping Identification and its Comparison for Various Types of Blade Couplings." In ASME Turbo Expo 2013: Turbine Technical Conference and Exposition. American Society of Mechanical Engineers, 2013. http://dx.doi.org/10.1115/gt2013-95438.

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Анотація:
Regarding steam turbine blade vibrations, damping of blade as well as bladed disc mode shapes is one of the most important parameters in terms of steam turbine operation. A value of the parameter depends on properties of material used for manufacturing and construction elements of the blades and the discs such as blade roots, shrouds, tiebosses (snubbers) and dampers. This article deals with a comparison of damping of mode shapes for particular blade couplings and shows which methods are suitable for determination of the damping in individual cases. The whole identification procedure of the damping together with its specifics is also presented. At first, an identification technique of material damping ratio is introduced and its results are given for different materials. The material damping ratio is assessed as material strain dependent. Subsequently, damping ratio of bladed disc mode shapes under bladed disc rotation is identified taking into account two alternatives. The alternatives differ in such a way that blades have been free for the first time and then coupled with friction dampers. Outcomes presented in the article illustrate good agreement between damping ratio of bladed disc mode shapes with free blades and material used for manufacturing of the blades. On the other hand, damping ratio of bladed disc mode shapes with friction dampers is significantly different and strongly dependent on blade vibration amplitudes as well as nodal diameters of bladed disc mode shapes. Finally, nonlinear behavior of the bladed disc has been revealed along large blade vibration amplitudes and higher nodal diameters of the disc. The non-linear behavior manifests itself in such a way that values of natural frequencies of the disc have become dependent on blade vibration amplitudes.
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10

Przysowa, R., and A. Tuzik. "Data Management Techniques for Blade Vibration Analysis." In 7th EVI-GTI International Gas Turbine Instrumentation Conference. Institution of Engineering and Technology, 2015. http://dx.doi.org/10.1049/cp.2015.1798.

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