Готові списки джерел за темами / Wind turbines Mathematical models

Добірка наукової літератури з теми "Wind turbines Mathematical models"

Автор: Grafiati
Опубліковано: 10 грудня 2022
Оновлено: 29 січня 2023

Оформте джерело за APA, MLA, Chicago, Harvard та іншими стилями

Оберіть тип джерела:

Зміст

Ознайомтеся зі списками актуальних статей, книг, дисертацій, тез та інших наукових джерел на тему "Wind turbines Mathematical models".

Біля кожної праці в переліку літератури доступна кнопка «Додати до бібліографії». Скористайтеся нею – і ми автоматично оформимо бібліографічне посилання на обрану працю в потрібному вам стилі цитування: APA, MLA, «Гарвард», «Чикаго», «Ванкувер» тощо.

Також ви можете завантажити повний текст наукової публікації у форматі «.pdf» та прочитати онлайн анотацію до роботи, якщо відповідні параметри наявні в метаданих.

Статті в журналах з теми "Wind turbines Mathematical models"

1

Năstase, Eugen-Vlad. "Studies on the Design Models of Horizontal Axis Wind Turbines." Bulletin of the Polytechnic Institute of Iași. Machine constructions Section 67, no. 1 (March 1, 2021): 9–18. http://dx.doi.org/10.2478/bipcm-2021-0001.

Повний текст джерела
Анотація:
Abstract The aim of the paper is to present through a contrastive analysis the main models used in the analysis and design of horizontal axis wind turbines. The basis for designing a rotor for a wind turbine, which is the main element of a turbine that extracts energy from the wind, is the propeller theory. This theory incorporates mathematical models that describe the movement of fluid around the propeller. The paper presents three generically named models, model A, model B and model C respectively, used in the analysis and design of the horizontal axis wind turbine’s rotor.
Стилі APA, Harvard, Vancouver, ISO та ін.
2

Hyman, Mario, and Mohd Hasan Ali. "A Novel Model for Wind Turbines on Trains." Energies 15, no. 20 (October 15, 2022): 7629. http://dx.doi.org/10.3390/en15207629.

Повний текст джерела
Анотація:
Wind turbines that are consistently exposed to the air displaced by moving trains have a high potential for energy generation. Researchers have developed mathematical models to simulate wind energy generation from turbines on moving trains but there are significant gaps in the developed model theory. Most models do not consider the negative effects that additional aerodynamic drag, increased weight, and modified dimensions can have on the train’s operation. To overcome the drawbacks of existing models, this work proposes a novel approach of modeling the wind turbines on trains by considering wind turbine exposure only when the train is decelerating or stationary. There are no models that consider all of these realistic physical effects as a function of time. Real-time analysis and power-system simulations showed that the proposed model could produce over 3 MJ of net energy for favorable train trips. The simulated load profile met the demand of a 1 KW generator connected to onboard electrical components. Some recommendations on possible future research on wind turbines on trains are explained.
Стилі APA, Harvard, Vancouver, ISO та ін.
3

Omar, Othman A. M., Hamdy M. Ahmed, and Reda A. Elbarkouky. "Commercial wind turbines modeling using single and composite cumulative probability density functions." International Journal of Electrical and Computer Engineering (IJECE) 11, no. 1 (February 1, 2021): 47. http://dx.doi.org/10.11591/ijece.v11i1.pp47-56.

Повний текст джерела
Анотація:
As wind turbines more widely used with newer manufactured types and larger electrical power scales, a brief mathematical modelling for these wind turbines operating power curves is needed for optimal site matching selections. In this paper, 24 commercial wind turbines with different ratings and different manufactures are modelled using single cumulative probability density functions modelling equations. A new mean of a composite cumulative probability density function is used for better modelling accuracy. Invasive weed optimization algorithm is used to estimate different models designing parameters. The best cumulative density function model for each wind turbine is reached through comparing the RMSE of each model. Results showed that Weibull-Gamma composite is the best modelling technique for 37.5% of the reached results.
Стилі APA, Harvard, Vancouver, ISO та ін.
4

Merizalde, Yuri, Luis Hernández-Callejo, Oscar Duque-Perez, and Víctor Alonso-Gómez. "Maintenance Models Applied to Wind Turbines. A Comprehensive Overview." Energies 12, no. 2 (January 11, 2019): 225. http://dx.doi.org/10.3390/en12020225.

Повний текст джерела
Анотація:
Wind power generation has been the fastest-growing energy alternative in recent years, however, it still has to compete with cheaper fossil energy sources. This is one of the motivations to constantly improve the efficiency of wind turbines and develop new Operation and Maintenance (O&M) methodologies. The decisions regarding O&M are based on different types of models, which cover a wide range of scenarios and variables and share the same goal, which is to minimize the Cost of Energy (COE) and maximize the profitability of a wind farm (WF). In this context, this review aims to identify and classify, from a comprehensive perspective, the different types of models used at the strategic, tactical, and operational decision levels of wind turbine maintenance, emphasizing mathematical models (MatMs). The investigation allows the conclusion that even though the evolution of the models and methodologies is ongoing, decision making in all the areas of the wind industry is currently based on artificial intelligence and machine learning models.
Стилі APA, Harvard, Vancouver, ISO та ін.
5

Saenz-Aguirre, Aitor, Ekaitz Zulueta, Unai Fernandez-Gamiz, Daniel Teso-Fz-Betoño, and Javier Olarte. "Kharitonov Theorem Based Robust Stability Analysis of a Wind Turbine Pitch Control System." Mathematics 8, no. 6 (June 12, 2020): 964. http://dx.doi.org/10.3390/math8060964.

Повний текст джерела
Анотація:
Wind energy has recently become one of the most prominent technologies among electrical energy generation systems. As a result, wind-based renewable energy generation systems are incessantly growing, and wind turbines of different characteristics are being installed in many locations around the world. One drawback associated with different characteristics of the wind turbines is that controllers have to be designed individually for each of them. Additionally, stable performance of the wind turbines needs to be ensured in the whole range of their operating conditions. Nowadays, there are many causes for uncertainties in the actual performance of a horizontal axis wind turbine, such as variations in the characteristics of the wind turbine, fabrication tolerances of its elements or non-linearities related to different operating-points. Hence, in order to respond to these uncertainties and ensure the stability of the wind turbine, robust control and stability theories have been gaining importance during recent years. Nevertheless, the use of robust stability analyses with complex wind turbine models still needs to be faced and remarkably improved. In this paper, a stability analysis of the pitch system control of a horizontal axis wind turbine based on the Kharitonov robust stability method is proposed. The objective was to assess the robust stability of a pitch controller in response to uncertainties arising from varying operating conditions of the National Renewable Energies Laboratory (NREL) 5 MW class IIA wind turbine. According to the results, the proposed method could satisfactorily respond to limited variations in the characteristics of the model, but could lack accuracy in cases of bigger variations or employment of high order complex mathematical models.
Стилі APA, Harvard, Vancouver, ISO та ін.
6

Tian, Xiange, Yongjian Jiang, Chen Liang, Cong Liu, You Ying, Hua Wang, Dahai Zhang, and Peng Qian. "A Novel Condition Monitoring Method of Wind Turbines Based on GMDH Neural Network." Energies 15, no. 18 (September 14, 2022): 6717. http://dx.doi.org/10.3390/en15186717.

Повний текст джерела
Анотація:
The safety of power transmission systems in wind turbines is crucial to the wind turbine’s stable operation and has attracted a great deal of attention in condition monitoring of wind farms. Many different intelligent condition monitoring schemes have been developed to detect the occurrence of defects via supervisory control and data acquisition (SCADA) data, which is the most commonly applied condition monitoring system in wind turbines. Normally, artificial neural networks are applied to establish prediction models of the wind turbine condition monitoring. In this paper, an alternative and cost-effective methodology has been proposed, based on the group method of data handling (GMDH) neural network. GMDH is a kind of computer-based mathematical modelling and structural identification algorithm. GMDH neural networks can automatically organize neural network architecture by heuristic self-organization methods and determine structural parameters, such as the number of layers, the number of neurons in hidden layers, and useful input variables. Furthermore, GMDH neural network can avoid over-fitting problems, which is a ubiquitous problem in artificial neural networks. The effectiveness and performance of the proposed method are validated in the case studies.
Стилі APA, Harvard, Vancouver, ISO та ін.
7

Podhurenko, V., Yu Kutsan, and V. Terekhov. "Modelling of cost indicators for wind turbines of multimegawatt class in various sizes." IOP Conference Series: Earth and Environmental Science 915, no. 1 (November 1, 2021): 012021. http://dx.doi.org/10.1088/1755-1315/915/1/012021.

Повний текст джерела
Анотація:
Abstract The choice of wind turbines to fit various specific wind conditions for the purpose of ensuring maximum generation of electric power at least investment expenditures is among the wind power sector overarching challenges. Solving this task involves the evaluation of cost indices for wind turbines of various sizes. A well-known and rather popular with investigators model, made by the National Renewable Energy Laboratory (USA) has been improved for the first time with the aim of determining the cost of wind turbines of various sizes on the basis of their main parameters (rated power, rotor diameter, hub height) for current conditions of application. The established correlation relationships between the cost of wind turbine and its main parameters made possible the transformation of a well-known complex model into a model with linear equations and minimization of computations. Based on the research studies of the evolution of wind turbines main parameters and an average (global) cost of 1 MW of their power, the authors have suggested the first-ever original linear mathematical models that enable evaluating the wind turbine cost for any year of research. In illustration of application of the first ever developed technique, we have made the assessment of operating efficiency of the US wind farms from 2010 to 2019. The results obtained convincingly indicate the high quality of the developed model.
Стилі APA, Harvard, Vancouver, ISO та ін.
8

Wisatesajja, Wongsakorn, Wirachai Roynarin, and Decha Intholo. "Comparing the Effect of Rotor Tilt Angle on Performance of Floating Offshore and Fixed Tower Wind Turbines." Journal of Sustainable Development 12, no. 5 (September 29, 2019): 84. http://dx.doi.org/10.5539/jsd.v12n5p84.

Повний текст джерела
Анотація:
The development of Floating Offshore Wind Turbines (FOWTs) aims to improve the potential performance of the wind turbine. However, a problem arises due to the angle of tilt from the wind flow and the floating platform, which leads to a vertical misalignment of the turbine axis, thereby reducing the available blade area and lowering the capacity to capture energy. To address this problem, this paper seeks to compare the influence of the rotor tilt angle on wind turbine performance between fixed tower wind turbines and FOWTs. The models used in the experiments have R1235 airfoil blades of diameter 84 cm. The experiment was analyzed using a wind tunnel and mathematical modelling techniques. Measurements were obtained using an angle meter, anemometer and tachometer. Testing involved wind speeds ranging from 2 m/s to 5.5 m/s, and the rotational speeds of the two turbine designs were compared. The study found that the rotational speeds of the FOWTs were lower than those of the fixed tower turbines. Moreover, at tilt angles from 3.5° – 6.1° there was a loss in performance which varied between 22% and 32% at different wind speeds. The tilt angle had a significant effect upon FOWTs due to the angle of attack was continuously changing, thus altering the optimal position of the turbine blades. This changing angle of attack caused the effective area of the rotor blade to change, leading to a reduction in power output at suboptimal angles. The study finally makes recommendations for future studies.
Стилі APA, Harvard, Vancouver, ISO та ін.
9

Al-Quraan, Ayman, and Bashar Al-Mhairat. "Intelligent Optimized Wind Turbine Cost Analysis for Different Wind Sites in Jordan." Sustainability 14, no. 5 (March 6, 2022): 3075. http://dx.doi.org/10.3390/su14053075.

Повний текст джерела
Анотація:
Choosing the right wind site and estimating the extracted energy of the wind turbines are essential to successfully establishing a wind farm in a specific wind site. In this paper, a method for estimating the extracted energy of the wind farms using several mathematical models is proposed. The estimating method, which was based on five wind turbines, Q1, Q2, Q3, Q4, and Q5 and three wind distribution models, gamma, Weibull, and Rayleigh, was used to suggest suitable specifications of a wind turbine for a specific wind site and maximize the extracted energy of the proposed wind farm. An optimization problem, developed for this purpose, was solved using the whale optimization algorithm (WOA). The suggested method was tested using several potential wind sites in Jordan. The proposed wind farms at these sites achieved the maximum extracted energy, maximum capacity factor (CF), and minimum levelized cost of energy (LCoE) based on the solution of the developed optimization problem. The developed model with Q3 and the Rayleigh distribution function was validated with real measurement data from several wind farms in Jordan. Error analysis showed that the difference between the measured and estimated energy was less than 20%. The study validated the provided model, which can now be utilized routinely for the assessment of wind energy potential at a specific wind site.
Стилі APA, Harvard, Vancouver, ISO та ін.
10

Krysiński, Tomasz, Zbigniew Buliński, and Andrzej J. Nowak. "Numerical modeling and preliminary validation of drag-based vertical axis wind turbine." Archives of Thermodynamics 36, no. 1 (March 1, 2015): 19–38. http://dx.doi.org/10.1515/aoter-2015-0002.

Повний текст джерела
Анотація:
Abstract The main purpose of this article is to verify and validate the mathematical description of the airflow around a wind turbine with vertical axis of rotation, which could be considered as representative for this type of devices. Mathematical modeling of the airflow around wind turbines in particular those with the vertical axis is a problematic matter due to the complex nature of this highly swirled flow. Moreover, it is turbulent flow accompanied by a rotation of the rotor and the dynamic boundary layer separation. In such conditions, the key aspects of the mathematical model are accurate turbulence description, definition of circular motion as well as accompanying effects like centrifugal force or the Coriolis force and parameters of spatial and temporal discretization. The paper presents the impact of the different simulation parameters on the obtained results of the wind turbine simulation. Analysed models have been validated against experimental data published in the literature.
Стилі APA, Harvard, Vancouver, ISO та ін.
Більше джерел

Дисертації з теми "Wind turbines Mathematical models"

1

Scott, Ryan. "Characterizing Tilt Effects on Wind Plants." PDXScholar, 2019. https://pdxscholar.library.pdx.edu/open_access_etds/5035.

Повний текст джерела
Анотація:
Tilting the nacelle of a wind turbine modifies entrainment into the wind plant and impacts total efficiency. Extreme angles can produce flying and crashing wakes where the wake either disrupts entertainment from the undisturbed flow above or is decimated on the ground. The effect of tilt angle on downstream wake behavior was investigated in a series of wind tunnel experiments. Scale model turbines with a hub height and diameter of 12 cm were arranged in a Cartesian array comprised of four rows of three turbines each. Nacelle tilt was varied in the third row from -15° to 15° in chosen 5° increments. Stereo PIV measurements of the instantaneous velocity field were recorded at four locations for each angle. Tilted wakes are described in terms of the average streamwise velocity field, wall-normal velocity field, Reynolds stresses, and mean vertical transport of kinetic energy. Conditional sampling is used to quantify the importance of sweep vs. ejection events and thus downwards vs. upwards momentum transfer. Additionally, wake center displacement and changes in net power are presented and compared to existing models. The results demonstrate large variations in wake velocity and vertical displacement with enhanced vertical energy and momentum transfer for negative tilt angles. Simulation models accurately predict wake deflection while analytic models deviate considerably highlighting the difficulties in describing tilt phenomena. Negative angles successfully produce crashing wakes and improve the availability of kinetic energy thereby improving the power output of the wind plant.
Стилі APA, Harvard, Vancouver, ISO та ін.
2

Fernando, Mahamarakkalage Saman Udaya Kumar. "On the performance and wake aerodynamics of the Savonius wind turbine." Thesis, University of British Columbia, 1987. http://hdl.handle.net/2429/27299.

Повний текст джерела
Анотація:
The objective of the thesis is to establish methodology for development of a wind turbine, simple in design and easy to maintain, for possible application in developing countries. To that end the Savonius configuration is analyzed in detail both experimentally and analytically to lay a sound foundation for its performance evaluation. Following a brief review of relevant significant contributions in the field (Chapter I), an extensive wind tunnel test-program using scale models is described which assesses the relative influence of system parameters such as blade geometry, gap-size, overlap, aspect ratio, Reynolds number, blockage, etc., on the rotor output. The parametric study leads to an optimum configuration with an increase in efficiency by around 100% compared to the reported efficiency of ≈ 12 — 15%. Of particular interest is the blockage correction procedure which is vital for application of the wind tunnel results to a prototype design, and facilitates comparison of data obtained by investigators using different models and test facilities. With the design and performance results in hand, Chapters III — VI focus attention on analytical approaches to complement the test procedure. Using the concept of a central vortex, substantiated by a flow visualization study, Chapter III develops a semi-empirical approach to predict the rotor performance using measured stationary blade pressure data. The objective here is to provide a simple yet reliable design tool which can replace dynamical testing with a significant saving in time, effort, and cost. The simple approach promises to be quite effective in predicting the rotor performance, even in the presence of blockage, and should prove useful at least in the preliminary design stages. Chapter IV describes in detail a relatively more sophisticated and rigorous Boundary Element Approach using the Discrete Vortex Model. The method attempts to represent the complex unsteady flow field with separating shear layers in a realistic fashion consistent with the available computational tools. Important steps in the numerical analysis of this challenging problem are discussed at some length in Chapter V and a performance evaluation algorithm established. Of considerable importance is the effect of computational parameters such as number of elements representing the rotor blade, time-step size, location of the nascent vortices, etc., on the accuracy of results and the associated cost. Results obtained using the Discrete Vortex Model are presented and discussed in Chapter VI, for both stationary as well as rotating Savonius configurations. A detailed parametric study provides fundamental information concerning the starting and dynamic torque time histories, power coefficient, evolution of the wake, Strouhal number, etc. A comparison with the flow visualization and wind tunnel test data (Chapter II) shows remarkable correlation suggesting considerable promise for the approach. The thesis ends with concluding remarks and a few suggestions concerning possible future research in the area.
Applied Science, Faculty of
Mechanical Engineering, Department of
Graduate
Стилі APA, Harvard, Vancouver, ISO та ін.
3

Zhu, Wenjin. "Maintenance of monitored systems with multiple deterioration mechanisms in dynamic environments : application to wind turbines." Thesis, Troyes, 2014. http://www.theses.fr/2014TROY0005/document.

Повний текст джерела
Анотація:
Les travaux présentés contribuent à la modélisation stochastique de la maintenance de systèmes mono- ou multi-composants à détériorations et à modes de défaillances multiples en environnement dynamique. Dans ce cadre, les contributions portent d'une part sur la modélisation des processus de défaillance, et d'autre part sur la proposition de structures de décision de maintenance intégrant les différents types d'information de surveillance en ligne disponible sur le système (état de détérioration mesuré ou reconstruit, état de l'environnement, ...) et le développement des modèles mathématiques d'évaluation associés. Les modèles de détérioration et de défaillances proposés pour les systèmes mono-composants permettent de rendre compte de sources de détérioration multiples (chocs et détérioration graduelle) et d'intégrer les effets de l'environnement sur la dégradation. Pour les systèmes multi-composants, on insiste sur les risques concurrents, indépendants ou dépendants et sur l'intégration de l'environnement. Les modèles de maintenance développés sont adaptés aux modèles de détérioration proposés et permettent de prendre en compte la contribution de chaque source de détérioration dans la décision de maintenance, ou d'intégrer de l'information de surveillance indirecte dans la décision, ou encore de combiner plusieurs types d'actions de maintenance. Dans chaque cas, on montre comment les modèles développés répondent aux problématiques de la maintenance de turbines et de parcs éoliens
The thesis contributes to stochastic maintenance modeling of single or multi-components deteriorating systems with several failure modes evolving in a dynamic environment. In one hand, the failure process modeling is addressed and in the other hand, the thesis proposes maintenance decision rules taking into account available on-line monitoring information (system state, deterioration level, environmental conditions …) and develops mathematical models to measure the performances of the latter decision rules.In the framework of single component systems, the proposed deterioration and failure models take into account several deterioration causes (chocks and wear) and also the impact of environmental conditions on the deterioration. For multi-components systems, the competing risk models are considered and the dependencies and the impact of the environmental conditions are also studied. The proposed maintenance models are suitable for deterioration models and permit to consider different deterioration causes and to analyze the impact of the monitoring on the performances of the maintenance policies. For each case, the interest and applicability of models are analyzed through the example of wind turbine and wind turbine farm maintenance
Стилі APA, Harvard, Vancouver, ISO та ін.
4

Hamilton, Nicholas Michael. "Wake Character in the Wind Turbine Array: (Dis-)Organization, Spatial and Dynamic Evolution and Low-dimensional Modeling." PDXScholar, 2016. http://pdxscholar.library.pdx.edu/open_access_etds/3084.

Повний текст джерела
Анотація:
To maximize the effectiveness of the rapidly increasing capacity of installed wind energy resources, new models must be developed that are capable of more nuanced control of each wind turbine so that each device is more responsive to inflow events. Models used to plan wind turbine arrays and control behavior of devices within the farm currently make questionable estimates of the incoming atmospheric flow and update turbine configurations infrequently. As a result, wind turbines often operate at diminished capacities, especially in arrays where wind turbine wakes interact and inflow conditions are far from ideal. New turbine control and wake prediction models must be developed to tune individual devices and make accurate power predictions. To that end, wind tunnel experiments are conducted detailing the turbulent flow in the wake of a wind turbine in a model-scale array. The proper orthogonal decomposition (POD) is applied to characterize the spatial evolution of structures in the wake. Mode bases from distinct downstream locations are reconciled through a secondary decomposition, called double proper orthogonal decomposition (DPOD), indicating that modes of common rank in the wake share an ordered set of sub-modal projections whose organization delineates underlying wake structures and spatial evolution. The doubly truncated basis of sub-modal structures represents a reduction to 0.015% of the total degrees of freedom of the wind turbine wake. Low-order representations of the Reynolds stress tensor are made using only the most dominant DPOD modes, corrected to account for energy excluded from the truncated basis with a tensor of constant coefficients defined to rescale the low-order representation of the stresses to match the original statistics. Data from the wind turbine wake are contrasted against simulation data from a fully-developed channel flow, illuminating a range of anisotropic states of turbulence. Complexity of flow descriptions resulting from truncated POD bases is suppressed in severe basis truncations, exaggerating anisotropy of the modeled flow and, in extreme cases, can lead to the loss of three dimensionality. Constant corrections to the low-order descriptions of the Reynolds stress tensor reduce the root-mean-square error between low-order descriptions of the flow and the full statistics as much as 40% and, in some cases, reintroduce three-dimensionality to severe truncations of POD bases. Low-dimensional models are constructed by coupling the evolution of the dynamic mode coefficients through their respective time derivatives and successfully account for non-linear mode interaction. Deviation between time derivatives of mode coefficients and their least-squares fit is amplified in numerical integration of the system, leading to unstable long-time solutions. Periodic recalibration of the dynamical system is undertaken by limiting the integration time and using a virtual sensor upstream of the wind turbine actuator disk in to read the effective inflow velocity. A series of open-loop transfer functions are designed to inform the low-order dynamical system of the flow incident to the wind turbine rotor. Validation data shows that the model tuned to the inflow reproduces dynamic mode coefficients with little to no error given a sufficiently small interval between instances of recalibration. The reduced-order model makes accurate predictions of the wake when informed of turbulent inflow events. The modeling scheme represents a viable path for continuous time feedback and control that may be used to selectively tune a wind turbine in the effort to maximize power output of large wind farms.
Стилі APA, Harvard, Vancouver, ISO та ін.
5

Melius, Matthew Scott. "Identification of Markov Processes within a Wind Turbine Array Boundary Layer." PDXScholar, 2013. https://pdxscholar.library.pdx.edu/open_access_etds/1422.

Повний текст джерела
Анотація:
The Markovianity within a wind turbine array boundary layer is explored for data taken in a wind tunnel containing a model wind turbine array. A stochastic analysis of the data is carried out using Markov chain theory. The data were obtained via hot-wire anemometry thus providing point velocity statistics. The theory of Markovian processes is applied to obtain a statistical description of longitudinal velocity increments inside the turbine wake using conditional probability density functions. It is found that two and three point conditional probability density functions are similar for scale differences larger than the Taylor micro-scale. This result is quantified by use of the Wilcoxon rank-sum test which verifies that this relationship holds independent of initial scale selection outside of the near-wake region behind a wind turbine. Furthermore, at the locations which demonstrate Markovian properties there is a well defined inertial sub-range which follows Kolmogorv's -5/3 scaling behavior. Results indicate an existence of Markovian properties at scales on the order of the Taylor micro-scale, λ for most locations in the wake. The exception being directly behind the tips of the rotor and the hub where the complex turbulent interactions characteristic of the near-wake demonstrate influence upon the Markov process. The presence of a Markov process in the remaining locations leads to characterization of the multi-point statistics of the wind turbine wakes using the most recent states of the flow.
Стилі APA, Harvard, Vancouver, ISO та ін.
6

Hamilton, Nicholas Michael. "Anisotropy of the Reynolds Stress Tensor in the Wakes of Counter-Rotating Wind Turbine Arrays." PDXScholar, 2014. https://pdxscholar.library.pdx.edu/open_access_etds/1848.

Повний текст джерела
Анотація:
A wind turbine array was constructed in the wind tunnel at Portland State University in a standard Cartesian arrangement. Configurations of the turbine array were tested with rotor blades set to rotate in either a clockwise or counter-clockwise sense. Measurements of velocity were made with stereo particle-image velocimetry. Mean statistics of velocities and Reynolds stresses clearly show the effect of direction of rotation of rotor blades for both entrance and exit row turbines. Rotational sense of the turbine blades is visible in the mean spanwise velocity W and the Reynolds shear stress -[macron over vw]. The normalized anisotropy tensor was decomposed yielding invariants [lowercase eta] and [lowercase xi], which are plotted onto the Lumley triangle. Invariants of the normalized Reynolds stress anisotropy tensor indicate that distinct characters of turbulence exist in regions of the wake following the nacelle and the rotor blade tips. Eigendecomposition of the tensor yields principle components and corresponding coordinate system transformations. Characteristic spheroids are composed with the eigenvalues from the decomposition yielding shapes predicted by the Lumley triangle. Rotation of the coordinate system defined by the eigenvectors demonstrates streamwise trends, especially trailing the top rotor tip and below the hub of the rotors. Direction of rotation of rotor blades is evidenced in the orientation of characteristic spheroids according to principle axes. The characteristic spheroids of the anisotropy tensor and their relate alignments varies between cases clearly seen in the inflows to exit row turbines. There the normalized Reynolds stress anisotropy tensor shows cumulative effects of the rotational sense of upstream turbines. Comparison between the invariants of the Reynolds stress anisotropy tensor and terms from the mean mechanical energy equation indicate a correlation between the degree of anisotropy and the regions of the wind turbine wakes where turbulence kinetic energy is produced. The flux of kinetic energy into the momentum-deficit area of the wake from above the canopy is associated with prolate characteristic spheroids. Flux upward into the wake from below the rotor area is associate with oblate characteristic spheroids. Turbulence in the region of the flow directly following the nacelle of the wind turbines demonstrates more isotropy compared to the regions following the rotor blades. The power and power coefficients for wind turbines indicate that flow structures on the order of magnitude of the spanwise turbine spacing that increase turbine efficiency depending on particular array configuration.
Стилі APA, Harvard, Vancouver, ISO та ін.
7

Pang, Zhongyuan. "Dynamic models for wind turbines." Thesis, Pang, Zhongyuan (2014) Dynamic models for wind turbines. Other thesis, Murdoch University, 2014. https://researchrepository.murdoch.edu.au/id/eprint/23213/.

Повний текст джерела
Анотація:
With the increase of wind power capacity, wind energy is now becoming an essential part of energy production system. High wind power penetration may increase the instability of grid due to the characteristic of wind. Fortunately, with the development of power electronics, it is possible to provide a relatively stable energy production by applying power electronics to wind turbine. Due to the complexity of wind turbine, a generic dynamic model of wind turbine can be helpful. The objective of the work is to develop a general wind turbine models that can be used for investigations. The report had tracked the theory of wind turbine and its development, three different kinds of wind turbine are included, which are fixed speed wind turbine, variable slip wind turbine and doubly-fed induction generator wind turbine. Fundamental working theory and a model built by Matlab was provided for each of technology. Assessment for the models was done to prove that it has the ability to reflect the characteristic of wind turbine. Despite from that, the models were done in three phase, so it has the ability to do with load flow analysis or grid stability.
Стилі APA, Harvard, Vancouver, ISO та ін.
8

Krysiński, Tomasz. "Mathematical modelling and shape optimisation of vertical axis wind turbines blades." Rozprawa doktorska, ISBN 978-83-61506-47-8, 2018. https://repolis.bg.polsl.pl/dlibra/docmetadata?showContent=true&id=53466.

Повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
9

Krysiński, Tomasz. "Mathematical modelling and shape optimisation of vertical axis wind turbines blades." Rozprawa doktorska, ISBN 978-83-61506-47-8, 2018. https://delibra.bg.polsl.pl/dlibra/docmetadata?showContent=true&id=53466.

Повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
10

Benjanirat, Sarun. "Computational studies of the horizontal axis wind turbines in high wind speed condition using advanced turbulence models." Diss., Available online, Georgia Institute of Technology, 2006, 2006. http://etd.gatech.edu/theses/available/etd-08222006-145334/.

Повний текст джерела
Анотація:
Thesis (Ph. D.)--Aerospace Engineering, Georgia Institute of Technology, 2007.
Samual V. Shelton, Committee Member ; P.K. Yeung, Committee Member ; Lakshmi N. Sankar, Committee Chair ; Stephen Ruffin, Committee Member ; Marilyn Smith, Committee Member.
Стилі APA, Harvard, Vancouver, ISO та ін.
Більше джерел

Книги з теми "Wind turbines Mathematical models"

1

Muyeen, S. M. Stability augmentation of a grid-connected wind farm. London: Springer, 2009.

Знайти повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
2

Muyeen, S. M. Stability augmentation of a grid-connected wind farm. London: Springer, 2009.

Знайти повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
3

Doubly fed induction machine: Modeling and control for wind energy generation applications. Hoboken, NJ: IEEE Press, 2011.

Знайти повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
4

Wuertz, David B. Editing wind profiler measurements. Boulder, Colo: U.S. Dept. of Commerce, National Oceanic and Atmospheric Administration, Environmental Research Laboratories, Wave Propagation Laboratory, 1989.

Знайти повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
5

Wuertz, David B. Editing wind profiler measurements. Boulder, Colo: U.S. Dept. of Commerce, National Oceanic and Atmospheric Administration, Environmental Research Laboratories, Wave Propagation Laboratory, 1989.

Знайти повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
6

Wuertz, David B. Editing wind profiler measurements. Boulder, Colo: U.S. Dept. of Commerce, National Oceanic and Atmospheric Administration, Environmental Research Laboratories, Wave Propagation Laboratory, 1989.

Знайти повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
7

Palagin, A. A. Modelirovanie funkt͡s︡ionalʹnogo sostoi͡a︡nii͡a︡ i diagnostika turboustanovok. Kiev: Nauk. dumka, 1991.

Знайти повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
8

Palagin, A. A. Imitat͡s︡ionnyĭ ėksperiment na matematicheskikh modeli͡a︡kh turboustanovok. Kiev: Nauk. dumka, 1986.

Знайти повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
9

Lewandowski, Janusz. Zagadnienia identyfikacji turbin parowych. Warszawa: Wydawnictwa Politechniki Warszawskiej, 1990.

Знайти повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
10

Vulʹman, F. A. Matematicheskoe modelirovanie teplovykh skhem paroturbinnykh ustanovok na ĖVM. Moskva: "Mashinostroenie", 1985.

Знайти повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
Більше джерел

Частини книг з теми "Wind turbines Mathematical models"

1

Asnaz, Melike Sultan Karasu, Bedri Yuksel, and Kadriye Ergun. "Optimal Siting of Wind Turbines in a Wind Farm." In Mathematical Modelling and Optimization of Engineering Problems, 115–37. Cham: Springer International Publishing, 2020. http://dx.doi.org/10.1007/978-3-030-37062-6_6.

Повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
2

He, Jianming, Lin Guan, and Xinming Fan. "Equivalent Models of Wind Farms with Fixed Speed Wind Turbines." In Lecture Notes in Electrical Engineering, 1055–63. New York, NY: Springer New York, 2013. http://dx.doi.org/10.1007/978-1-4614-4981-2_114.

Повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
3

Frunzulica, F., H. Dumitrescu, A. Dumitrache, and V. Cardos. "An Advanced Aeroelastic Model for Horizontal Axis Wind Turbines." In Progress in Industrial Mathematics at ECMI 2008, 851–56. Berlin, Heidelberg: Springer Berlin Heidelberg, 2010. http://dx.doi.org/10.1007/978-3-642-12110-4_136.

Повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
4

Ferrer, Esteban, and Soledad Le Clainche. "Simple Models for Cross Flow Turbines." In Recent Advances in CFD for Wind and Tidal Offshore Turbines, 1–10. Cham: Springer International Publishing, 2019. http://dx.doi.org/10.1007/978-3-030-11887-7_1.

Повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
5

De Tommasi, Luciano, and Madeleine Gibescu. "On a Wind Farm Aggregate Model Based on the Output Rescaling of a Single Turbine Model." In Mathematics in Industry, 553–59. Berlin, Heidelberg: Springer Berlin Heidelberg, 2012. http://dx.doi.org/10.1007/978-3-642-25100-9_64.

Повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
6

Slew, K. Lee, M. Miller, A. Fereidooni, P. Tawagi, G. El-Hage, M. Hou, and E. Matida. "A Dual-Rotor Horizontal Axis Wind Turbine In-House Code (DR_HAWT)." In Mathematical and Computational Approaches in Advancing Modern Science and Engineering, 493–503. Cham: Springer International Publishing, 2016. http://dx.doi.org/10.1007/978-3-319-30379-6_45.

Повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
7

Serrano-Barreto, Carlos L., Jesús Enrique Sierra-García, and Matilde Santos. "Intelligent Hybrid Controllers for the Blade Angle of Floating Wind Turbines." In 16th International Conference on Soft Computing Models in Industrial and Environmental Applications (SOCO 2021), 461–70. Cham: Springer International Publishing, 2021. http://dx.doi.org/10.1007/978-3-030-87869-6_44.

Повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
8

Martínez, Alejandro Zornoza, Jesus Martínez-Gómez, and José A. Gámez. "A Data-Driven Approach for Components Useful Life Estimation in Wind Turbines." In 16th International Conference on Soft Computing Models in Industrial and Environmental Applications (SOCO 2021), 37–47. Cham: Springer International Publishing, 2021. http://dx.doi.org/10.1007/978-3-030-87869-6_4.

Повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
9

Roccia, Bruno A., Alejandro Cosimo, Sergio Preidikman, and Olivier Brüls. "Numerical Models for the Static Analysis of Cable Structures Used in Airborne Wind Turbines." In Multibody Mechatronic Systems, 140–47. Cham: Springer International Publishing, 2020. http://dx.doi.org/10.1007/978-3-030-60372-4_16.

Повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
10

Rueda, José Luis, Abdul W. Korai, Jaime C. Cepeda, István Erlich, and Francisco M. Gonzalez-Longatt. "Implementation of Simplified Models of DFIG-Based Wind Turbines for RMS-Type Simulation in DIgSILENT PowerFactory." In PowerFactory Applications for Power System Analysis, 197–220. Cham: Springer International Publishing, 2014. http://dx.doi.org/10.1007/978-3-319-12958-7_9.

Повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.

Тези доповідей конференцій з теми "Wind turbines Mathematical models"

1

Bolte, Ekkehard, and Matthias Landwehr. "Mathematical model of small wind turbines." In 2014 Ninth International Conference on Ecological Vehicles and Renewable Energies (EVER). IEEE, 2014. http://dx.doi.org/10.1109/ever.2014.6844151.

Повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
2

Reyes, V., J. J. Rodriguez, O. Carranza, and R. Ortega. "Review of mathematical models of both the power coefficient and the torque coefficient in wind turbines." In 2015 IEEE 24th International Symposium on Industrial Electronics (ISIE). IEEE, 2015. http://dx.doi.org/10.1109/isie.2015.7281688.

Повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
3

Kuo, Jim Y. J., David A. Romero, and Cristina H. Amon. "A Novel Wake Interaction Model for Wind Farm Layout Optimization." In ASME 2014 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 2014. http://dx.doi.org/10.1115/imece2014-39073.

Повний текст джерела
Анотація:
Optimizing the turbine layout in a wind farm is crucial to minimize wake interactions between turbines, which can lead to a significant reduction in power generation. This work is motivated by the need to develop wake interaction models that can accurately capture the wake losses in an array of wind turbines, while remaining computationally tractable for layout optimization studies. Among existing wake interaction models, the sum of squares (SS) model has been reported to be the most accurate. However, the SS model is unsuitable for wind farm layout optimization using mathematical programming methods, as it leads to non-linear objective functions. Hence, previous work has relied on approximated power calculations for optimization studies. In this work, we propose a mechanistic linear model for wake interactions based on energy balance, with coefficients determined based on publicly available data from the Horns Rev wind farm. A series of numerical tests was conducted using test cases from the wind farm layout optimization literature. Results show that the proposed model is solvable using standard mathematical programming methods, and resulted in turbine layouts with higher efficiency than those found by previous work.
Стилі APA, Harvard, Vancouver, ISO та ін.
4

Alinot, Cedric, and Christian Masson. "Aerodynamic Simulations of Wind Turbines Operating in Atmospheric Boundary Layer With Various Thermal Stratifications." In ASME 2002 Wind Energy Symposium. ASMEDC, 2002. http://dx.doi.org/10.1115/wind2002-42.

Повний текст джерела
Анотація:
This paper presents a numerical method for performance predictions of wind turbines immersed into stable, neutral, or unstable atmospheric boundary layer. Tile flowfield around a turbine is described by the Reynolds’ averaged Navier-Stokes equations complemented by the k-ε turbulence model. The density variations are introduced into the momentum equation using the Boussinesq approximation and appropriate buoyancy terms are included into the k and ε equations. An original expression for the closure coefficient related to the buoyancy production term is proposed in order to improve the accuracy of the simulations. The turbine is idealized as actuator disk surface, on which external surficial forces exerted by the turbine blade on the flow are prescribed according to the blade element theory. The resulting mathematical model has been implemented in FLUENT. The results presented in the paper include the power output and wake development under various thermal stratifications of an isolated wind turbine. In stable stratification, the power output is 4% lower than in neutral condition, while in unstable situation, the power is 3% larger. The predicted wake velocity defects are qualitatively in agreement with experimental observations.
Стилі APA, Harvard, Vancouver, ISO та ін.
5

Tamarit, F., E. Garcia, A. Correcher, E. Quiles, and F. Morant. "Mathematical Model of a Cogeneration System composed of a Floating Wind Turbine and Two Marine Current Turbines." In 2018 7th International Conference on Systems and Control (ICSC). IEEE, 2018. http://dx.doi.org/10.1109/icosc.2018.8587829.

Повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
6

Spahic, E., J. Morren, G. Balzer, and G. Michalke. "Mathematical Model of the Double Fed Induction Generator for Wind Turbines and its Control Quality." In 2007 International Conference on Power Engineering, Energy and Electrical Drives. IEEE, 2007. http://dx.doi.org/10.1109/powereng.2007.4380111.

Повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
7

Schmitz, Johannes, Milos Vukovic, and Hubertus Murrenhoff. "Hydrostatic Transmission for Wind Turbines: An Old Concept, New Dynamics." In ASME/BATH 2013 Symposium on Fluid Power and Motion Control. American Society of Mechanical Engineers, 2013. http://dx.doi.org/10.1115/fpmc2013-4449.

Повний текст джерела
Анотація:
Hydrostatic drives are commonly used in mobile machinery. A new application for this technology is the renewable energy sector, especially wind power. Despite using the same basic components the dynamics of these new drive systems are somewhat different compared to those used in mobile applications. In order to design an appropriate control system for a wind turbine it is necessary to understand these differences and how they affect the system. In this paper, the system behavior of a hydrostatic transmission for wind turbines is compared to commonly used hydrostatic drives in mobile machinery. The analysis begins by explaining that the characteristics of the loading acting on a turbine are fundamentally different to the load torque present in a standard application. Using mathematical models of both systems these differences are highlighted and discussed with special reference to how changes in system parameters can affect stability and lead to non-minimum phase behavior. These theoretical results are validated using measurements of a 1 MW hydrostatic transmission installed on a test bench.
Стилі APA, Harvard, Vancouver, ISO та ін.
8

Salwa, Tomasz, Onno Bokhove, and Mark A. Kelmanson. "Variational Modelling of Wave-Structure Interactions for Offshore Wind Turbines." In ASME 2016 35th International Conference on Ocean, Offshore and Arctic Engineering. American Society of Mechanical Engineers, 2016. http://dx.doi.org/10.1115/omae2016-54897.

Повний текст джерела
Анотація:
We consider the development of a mathematical model of water waves interacting with the mast of an offshore wind turbine. A variational approach is used for which the starting point is an action functional describing a dual system comprising a potential-flow fluid, a solid structure modelled with (linear) elasticity, and the coupling between them. The variational principle is applied and discretized directly using Galerkin finite elements that are continuous in space and dis/continuous in time. We develop a linearized model of the fluid-structure or wave-mast coupling, which is a linearization of the variational principle for the fully coupled nonlinear model. Our numerical results indicate that our variational approach yields a stable numerical discretization of a fully coupled model of water waves and a linear elastic beam. The energy exchange between the subsystems is seen to be in balance, yielding a total energy that shows only small and bounded oscillations whose amplitude tends to zero as the timestep goes to zero.
Стилі APA, Harvard, Vancouver, ISO та ін.
9

de Oliveira, Éverton L., Celso P. Pesce, Bruno Mendes, Renato M. M. Orsino, and Guilherme R. Franzini. "A Reduced-Order Mathematical Model for the Current-Induced Motion of a Floating Offshore Wind Turbine." In ASME 2021 3rd International Offshore Wind Technical Conference. American Society of Mechanical Engineers, 2021. http://dx.doi.org/10.1115/iowtc2021-3503.

Повний текст джерела
Анотація:
Abstract Floating offshore platforms motions induced by currents are quite complex phenomena, in general. In particular, VIM, Vortex-Induced Motion, is a type often encountered in platforms with circular columns. Recently, VIM has been observed in towing tank tests with a small-scale model of a Floating Offshore Wind Turbine (FOWT), the OC4 Phase II floater, a 3+1 columns platform. The present paper proposes a reduced-order mathematical model (ROM) to assess VIM of a FOWT. The ROM is derived on the horizontal plane, including yaw motions and nonlinear mooring forces. Current forces are represented through ‘wake variables’, adapting phenomenological models firstly used for VIM of mono-column platforms. The ROM is built upon a set of eleven generalized coordinates, three for the rigid body motion on the horizontal plane and a pair of wake variables for each column, resulting in a system of eleven nonlinear second-order ODEs. The pairs of wake variables obey van der Pol equations, and use hydrodynamic coefficients and parameters obtained from previous experiments with small draught cylinders. Hydro-dynamic interferences among columns or heave plates effects on the flow are not considered, for simplicity. The validity of the proposed model is assessed having the mentioned small-scale experimental campaign as a case study. The simulations are carried out at three different current incidence angles, 0, 90 and 180 degrees, spanning a large range of reduced velocities. The simulations reproduce well the oscillations observed in the experimental tests. A good agreement in transverse oscillations is found, including lock-in regions. The simulations also depict a possibly important phenomenon: a resonant yaw motion emerging at high reduced velocities.
Стилі APA, Harvard, Vancouver, ISO та ін.
10

Vella, Peter P., Tonio Sant, and Robert N. Farrugia. "Integrating Compressed Air Energy Storage (CAES) in Floating Offshore Wind Turbines." In ASME 2019 2nd International Offshore Wind Technical Conference. American Society of Mechanical Engineers, 2019. http://dx.doi.org/10.1115/iowtc2019-7533.

Повний текст джерела
Анотація:
Abstract The design of an offshore energy storage system carries unknowns which need to be studied at an early stage of the project to avoid unnecessary costs of failures. These risks have led to an increasing dependence on more sophisticated mathematical models. This paper refers specifically to energy storage in the offshore wind farming industry and has the objective of proposing an adiabatic compressed air energy (A-CAES) system which would be integrated on a semi-submersible offshore wind turbine (OWT) platform. Calculations in respect to the sizing of the main sub-components of the system are included and estimates for the overall round trip efficiency are presented. Preliminary calculations to size the various parts of the energy storage system (ESS) have been carried out based on the energy availability of an offshore 8 MW wind turbine with real wind data from the North Sea. The load data to determine the lowest 12-hour demand period was taken from the Nordpool database. The calculations of the proposed conceptual design are based on an operational scenario in which the 24-hour period of a particular day is split in a 12-hour charging and 12-hour discharging cycle. For charging, a 5-bank, 2-stage compressor train is used to pressurize a number of steel cylindrical vessels with compressed air. This is followed by a process in which the compressed air is discharged across 12 hours using a 2-bank, 2-stage expander turbine. The multiple compression banks enable a modular power delivery to the air storage vessels, with the number of compressors utilized varying subject to wind availability. The two stages allowed for the air to be cooled in between the stages using heat exchangers, transferring the heat of compression to a pressurized sea water circuit. The hot water would be stored in thermally insulated vessels at 350°C to heat the inlet expanding air in the discharge period. A 70 and 100 Bar charging scenarios, both with a cushion pressure (CP) in the air storage vessel (ASV) of 10 Bar at the end of the discharge cycle have been considered. Standard performance criteria are calculated such as compression and expansion ratios, inlet and outlet temperatures for the respective expansion and compression air streams and flow rates within the heat exchangers to come up with an indicative sizing proposal for the respective turbo machinery and storage vessels making up the system. Round trip efficiencies are also calculated. The study determined that a CAES system consisting of 9 compressed air storage vessels operating with a peak pressure of 100 Bar should meet the storage requirements. It is also estimated that the entire CAES system would require around 1082 m2 of deck area on the platform to accommodate the pressure vessels, the compressor and expander trains, the heat exchanger and the hot water storage vessel.
Стилі APA, Harvard, Vancouver, ISO та ін.

Звіти організацій з теми "Wind turbines Mathematical models"

1

Singh, Mohit, and Surya Santoso. Dynamic Models for Wind Turbines and Wind Power Plants. Office of Scientific and Technical Information (OSTI), October 2011. http://dx.doi.org/10.2172/1028524.

Повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
2

Author, Not Given. NREL Computer Models Integrate Wind Turbines with Floating Platforms (Fact Sheet). Office of Scientific and Technical Information (OSTI), July 2011. http://dx.doi.org/10.2172/1018877.

Повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
3

Barnard, J. C. An evaluation of three models designed for siting wind turbines in areas of complex terrain. Office of Scientific and Technical Information (OSTI), June 1990. http://dx.doi.org/10.2172/6853604.

Повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
Також вас можуть зацікавити розширені добірки на тему "Wind turbines Mathematical models" для конкретних типів джерел:
Статті в журналах Дисертації Книги
Ми пропонуємо знижки на всі преміум-плани для авторів, чиї праці увійшли до тематичних добірок літератури. Зв'яжіться з нами, щоб отримати унікальний промокод!

До бібліографії