China wind atlas was made by numerical simulation and the wind energy potential in China was calculated. The model system for wind energy resource assessment was set up based on Canadian Wind Energy Simulating Toolkit...China wind atlas was made by numerical simulation and the wind energy potential in China was calculated. The model system for wind energy resource assessment was set up based on Canadian Wind Energy Simulating Toolkit (WEST) and the simulating method was as follows. First, the weather classes were obtained depend on meteorological data of 30 years. Then, driven by the initial meteorological field produced by each weather class, the meso-scale model ran for the distribution of wind energy resources according each weather class condition one by one. Finally, averaging all the modeling output weighted by the occurrence frequency of each weather class, the annual mean distribution of wind energy resources was worked out. Compared the simulated wind energy potential with other results from several activities and studies for wind energy resource assessment, it is found that the simulated wind energy potential in mainland of China is 3 times that from the second and the third investigations for wind energy resources by CMA, and is similar to the wind energy potential obtained by NREL in Solar and Wind Energy Resource Assessment(SWERA) project. The simulated offshore wind energy potential of China seems smaller than the true value. According to the simulated results of CMA and considering lots of limited factors to wind energy development, the final conclusion can be obtained that the wind energy availability in China is 700～1 200 GW, in which 600～1 000 GW is in mainland and 100～200 GW is on offshore, and wind power will become the important part of energy composition in future.展开更多
Wind energy is a kind of clean renewable energy, which is also relatively mature in technology, with largescale development conditions and prospect for the commercialization. The development of wind energy is a system...Wind energy is a kind of clean renewable energy, which is also relatively mature in technology, with largescale development conditions and prospect for the commercialization. The development of wind energy is a systematic project, involving policy, law, technology, economy, society, environment, education and other aspects. The relationship among all the aspects should be well treated and coordinated. This paper has discussed the following relationships which should be well coordinated: relationship between wind resources and wind energy development, relationship between the wind turbine generator system and the components, relationship between wind energy technology and wind energy industry, relationship between off-grid wind power and grid-connected wind power, relationship between wind farm and the power grid, relationship between onshore wind power and offshore wind power, relationship between wind energy and other energies, relationship between technology introduction and self-innovation, relationship among foreign-funded, joint ventured and domestic-funded enterprises and relationship between the government guidance and the market regulation, as well as giving out some suggestions.展开更多
Complicated loads encountered by floating offshore wind turbines(FOWTs)in real sea conditions are crucial for future optimization of design,but obtaining data on them directly poses a challenge.To address this issue,w...Complicated loads encountered by floating offshore wind turbines(FOWTs)in real sea conditions are crucial for future optimization of design,but obtaining data on them directly poses a challenge.To address this issue,we applied machine learning techniques to obtain hydrodynamic and aerodynamic loads of FOWTs by measuring platform motion responses and wave-elevation sequences.First,a computational fluid dynamics(CFD)simulation model of the floating platform was established based on the dynamic fluid body interaction technique and overset grid technology.Then,a long short-term memory(LSTM)neural network model was constructed and trained to learn the nonlinear relationship between the waves,platform-motion inputs,and hydrodynamic-load outputs.The optimal model was determined after analyzing the sensitivity of parameters such as sample characteristics,network layers,and neuron numbers.Subsequently,the effectiveness of the hydrodynamic load model was validated under different simulation conditions,and the aerodynamic load calculation was completed based on the D'Alembert principle.Finally,we built a hybrid-scale FOWT model,based on the software in the loop strategy,in which the wind turbine was replaced by an actuation system.Model tests were carried out in a wave basin and the results demonstrated that the root mean square errors of the hydrodynamic and aerodynamic load measurements were 4.20%and 10.68%,respectively.展开更多
Vector winds play a crucial role in weather and climate,as well as the effective utilization of wind energy resources.However,limited research has been conducted on treating the wind field as a vector field in the eva...Vector winds play a crucial role in weather and climate,as well as the effective utilization of wind energy resources.However,limited research has been conducted on treating the wind field as a vector field in the evaluation of numerical weather prediction models.In this study,the authors treat vector winds as a whole by employing a vector field evaluation method,and evaluate the mesoscale model of the China Meteorological Administration(CMA-MESO)and ECMWF forecast,with reference to ERA5 reanalysis,in terms of multiple aspects of vector winds over eastern China in 2022.The results show that the ECMWF forecast is superior to CMA-MESO in predicting the spatial distribution and intensity of 10-m vector winds.Both models overestimate the wind speed in East China,and CMA-MESO overestimates the wind speed to a greater extent.The forecasting skill of the vector wind field in both models decreases with increasing lead time.The forecasting skill of CMA-MESO fluctuates more and decreases faster than that of the ECMWF forecast.There is a significant negative correlation between the model vector wind forecasting skill and terrain height.This study provides a scientific evaluation of the local application of vector wind forecasts of the CMA-MESO model and ECMWF forecast.展开更多
In the past,the lightning strike risk assessment of wind farms mainly referred to the Lightning Protection Part 2:Risk Management(IEC 62305-2-2010)and the Lightning Protection of Wind Energy System(IEC 61400-24-2019)b...In the past,the lightning strike risk assessment of wind farms mainly referred to the Lightning Protection Part 2:Risk Management(IEC 62305-2-2010)and the Lightning Protection of Wind Energy System(IEC 61400-24-2019)based on protection angle method.In fact,the basic idea of the two is the same,that is,the source of the lightning fan is replaced by S1-S4 of the former lightning building with the latter ND-NDJ.According to the above method of wind farm evaluation,it has been proved that the practice can not achieve good results.Taking offshore wind farm as an example,this paper introduces a new method of establishing six evaluation indicators to determine the risk level according to the new technology and compliance principle of regional lightning protection(semi-circular method),which can be used for reference by wind farm technicians.展开更多
Improving the accuracy of the evaluation of the performance of wind farms in large wind power bases located in complex terrain under the actual atmosphere is crucial to the sustainable development of wind power.To thi...Improving the accuracy of the evaluation of the performance of wind farms in large wind power bases located in complex terrain under the actual atmosphere is crucial to the sustainable development of wind power.To this end,this study combined the Weather Research and Forecasting(WRF)model with the Wind Farm Parameterization(WFP)method to investigate the wake characteristics and operational performance of large onshore wind farms in the complex terrain of Jiuquan City,Gansu Province,China.The research results showed that after verification,the systematic error of the WRF simulations was less than 3%.The WRF model and the WFP scheme simulated a significant warming phenomenon within the wind power base area,while a cooling effect was observed outside.The analysis of the wake effects indicated that the impact of PhaseⅠconstruction on PhaseⅡconstruction of the wind power base was minimal.During the operation of the entire wind power base,the wind speed within the wind farm decreased by approximately 10%,and the influence range of the predominant wind direction extended over a hundred kilometers downwind.The research conclusions provide a powerful scientific basis for optimizing design and operation,improving efficiency,minimizing the negative impacts on adjacent wind turbines,and ensuring the sustainable development of wind energy through dynamic planning and scientific assessment.展开更多
A downburst is a strong downdraft generated by intense thunderstorm clouds,producing radially divergent and highly destructive winds near the ground.Its characteristic scales are expressed through random variations in...A downburst is a strong downdraft generated by intense thunderstorm clouds,producing radially divergent and highly destructive winds near the ground.Its characteristic scales are expressed through random variations in jet height,velocity,and diameter during an event.In this study,a reduced-scale parked wind turbine is exposed to downburst wind fields to investigate the resulting extreme wind loads.The analysis emphasizes both the flow structure of downbursts and the variations of surface wind pressure on turbine blades under different jet parameters.Results show that increasing jet velocity markedly enhances the maximum horizontal wind speed,while greater jet height reduces the horizontal wind speed and shifts the peak velocity closer to the jet center.Increasing jet diameter primarily affects the radial position of the maximum horizontal wind speed.For the wind turbine,the maximum equivalent stress and blade displacement increase almost linearly with jet velocity,but exhibit the opposite trend with jet diameter.Specifically,as jet velocity rises from 10 m/s to 20 m/s,the surface pressure coefficient at the blade tip increases by approximately 4.5 times.Changes in jet diameter indirectly alter the turbine’s relative position within the wind field,leading to variations in wind load direction and exposure area.Conversely,increasing jet height extends the dissipation path of the downdraft,thereby reducing the intensity of the airflow acting on the blades.For example,when jet height increases from 0.3 m to 1.2 m,the surface pressure coefficient at the blade tip decreases by nearly 50%.展开更多
In order to investigate the wind characteristics of coastal areas of China, a long-term field measurement of natural wind was carried out. Based on the field measurement results, this paper presents the natural wind c...In order to investigate the wind characteristics of coastal areas of China, a long-term field measurement of natural wind was carried out. Based on the field measurement results, this paper presents the natural wind characteristics of typhoons and strong monsoons at the site of Xi-hou-men Bridge, including mean wind speed, mean wind direction, mean wind elevation angle, turbulent intensity, gust factor, turbulence integral length scales, power spectrum of wind speed and spatial correlation of gusty wind, the profiles of mean wind speed and turbulent intensity, etc. The correlation among wind characteristics is analyzed in detail, and the similarities and differences of wind characteristics between typhoons and monsoons are analyzed. These results can pro- vide detailed wind characteristics of coastal areas of China.展开更多
Present of wind power is sporadically and cannot be utilized as the only fundamental load of energy sources.This paper proposes a wind-solar hybrid energy storage system(HESS)to ensure a stable supply grid for a longe...Present of wind power is sporadically and cannot be utilized as the only fundamental load of energy sources.This paper proposes a wind-solar hybrid energy storage system(HESS)to ensure a stable supply grid for a longer period.A multi-objective genetic algorithm(MOGA)and state of charge(SOC)region division for the batteries are introduced to solve the objective function and configuration of the system capacity,respectively.MATLAB/Simulink was used for simulation test.The optimization results show that for a 0.5 MW wind power and 0.5 MW photovoltaic system,with a combination of a 300 Ah lithium battery,a 200 Ah lead-acid battery,and a water storage tank,the proposed strategy reduces the system construction cost by approximately 18,000 yuan.Additionally,the cycle count of the electrochemical energy storage systemincreases from4515 to 4660,while the depth of discharge decreases from 55.37%to 53.65%,achieving shallow charging and discharging,thereby extending battery life and reducing grid voltage fluctuations significantly.The proposed strategy is a guide for stabilizing the grid connection of wind and solar power generation,capability allocation,and energy management of energy conservation systems.展开更多
This paper presents an analysis of a pre-feasibility study of a 10 MW offshore wind power project in Nakhon Si Thammarat province, southern Thailand. The wind speeds at the hub heights of large scale wind turbine gene...This paper presents an analysis of a pre-feasibility study of a 10 MW offshore wind power project in Nakhon Si Thammarat province, southern Thailand. The wind speeds at the hub heights of large scale wind turbine generators （WTG）, i.e. 80-100 m, were extrapolated using monthly mean wind shear coefficients and the l/7th exponent. Using WAsP 9.0, the annual energy production from several models of offshore wind farms using different WTG was analyzed. The capacity factor and the cost of energy were then computed. Using best available estimates, the analysis shows that the estimated annual mean offshore wind speeds at 80-100 m were in the range of 6.4 and 8.3 m/s. The annual energy production by the wind farm from nine models of wind turbine generators were in the range of 20-39 GWh/year, corresponding to a capacity factor in the range of 26-46%, while the cost of energy was 12-15 US cent/kWh.展开更多
Traditional gust load factor(GLF)method,inertial wind load(IWL)method and tri-component method(LRC+IWL)cannot accurately analyze the wind-induced responses of super-large cooling towers,so the real combination formula...Traditional gust load factor(GLF)method,inertial wind load(IWL)method and tri-component method(LRC+IWL)cannot accurately analyze the wind-induced responses of super-large cooling towers,so the real combination formulas of fluctuating wind-induced responses and equivalent static wind loads(ESWLSs)were derived based on structural dynamics and random vibration theory.The consistent coupled method(CCM)was presented to compensate the coupled term between background and resonant response.Taking the super-large cooling tower(H=215 m)of nuclear power plant in Jiangxi Province,China,which is the highest and largest in China,as the example,based on modified equivalent beam-net design method,the aero-elastic model for simultaneous pressure and vibration measurement of super-large cooling tower is firstly carried out.Then,combining wind tunnel test and CCM,the effects of self-excited force on the surface pressures and wind-induced responses are discussed,and the wind-induced response characteristics of background component,resonant component,coupled term between background and resonant response,fluctuating responses,and wind vibration coefficients are discussed.It can be concluded that wind-induced response mechanism must be understood to direct the wind resistant design for super-large cooling towers.展开更多
Two trains passing each other is controlling factor for the wind-vehicle-bridge systems.To test the aerodynamic characteristics of moving vehicles under crosswinds when two trains are passing each other,a wind tunnel ...Two trains passing each other is controlling factor for the wind-vehicle-bridge systems.To test the aerodynamic characteristics of moving vehicles under crosswinds when two trains are passing each other,a wind tunnel test device,which has two moving tracks,was developed.The rationality of the test result was discussed,the effects of intersection mode,yaw angle and lane spacing on the aerodynamic coefficients of the leeward train were analyzed,and the difference of aerodynamic coefficients between the head vehicle and the tail vehicle was discussed.The results show that the proposed test device has good repeatability.The intersection modes have a certain effect on the aerodynamic force of the leeward train when two trains are passing each other,and the results should be more reasonable during the two trains dynamic passing each other.With the decrease of yaw angle,the sudden change of train aerodynamic coefficients is more obvious.The decrease of lane spacing will increase the sudden change of leeward vehicles.In the process of two trains passing each other,the aerodynamic coefficients of the head vehicle and tail vehicle are significantly different,so the coupling vibration analysis of wind-vehicle-bridge system should be considered separately.展开更多
Under natural conditions, wind turbines are inevitably eroded by the action of sand-wind flow. To further investigate the effects of dust drift on the erosion of the wind turbine blades in sand-wind environments~ the ...Under natural conditions, wind turbines are inevitably eroded by the action of sand-wind flow. To further investigate the effects of dust drift on the erosion of the wind turbine blades in sand-wind environments~ the effects of the wind velocity, particle diameter, and particle density on the erosion of wind turbine airfoils are studied, and the effects of the particle Stokes number on the airfoil erosion are discussed. The results show that, when the angle of attack （AOA） is 6.1~, there will be no erosion on the airfoil surface if the particle Stokes number is lower than 0.013 5, whereas erosion will occur if the particle Stokes number is higher than 0.015 1. Therefore, there exists a critical range for the particle Stokes number. When the particle Stokes number is higher than the maximum value in the critical range, airfoil erosion will occur. The result is further confirmed by changing the particle diameter, particle density, and inflow speed. It is shown that the erosion area on the airfoil and the maximum erosion rate are almost equal under the same particle Stokes number and AOA. The extent of airfoil erosion increases when the particle Stokes number increases, and the critical particle Stokes number increases when the AOA increases. Moreover, the geometric shape of the airfoil pressure surface greatly affects the airfoil erosion, especially at the curvature near the leading edge.展开更多
The optimization of turbine blades is crucial in improving the efficiency of wind energy systems and developing clean energy production models.This paper presented a novel approach to the structural design of smallsca...The optimization of turbine blades is crucial in improving the efficiency of wind energy systems and developing clean energy production models.This paper presented a novel approach to the structural design of smallscale turbine blades using the Artificial Bee Colony(ABC)Algorithm based on the stochastic method to optimize both mass and cost(objective functions).The study used computational fluid dynamics(CFD)and structural analysis to consider the fluid-structure interaction.The optimization algorithm defined several variables:structural constraints,the type of composite material,and the number of composite layers to form a mathematical model.The numerical modeling was performed using the Ansys Fluent software and its Fluid-Structure Interaction(FSI)module.The ANSYS Composite PrePost(ACP)advanced composite modeling method was utilized in the structural design of composite materials.This study showed that the structurally optimized small-scale turbine blades provided a sustainable solution with improved efficiency compared to traditional designs.Furthermore,using CFD,structural analysis,and material characterization techniques first considered in this study highlights the importance of considering structural behavior when optimizing turbine blade designs.展开更多
Wind turbine size has increased continuously and correspondingly also its Reynolds numbers. The Reynolds number effect can therefore no longer be ignored in design and optimization of wind turbines. Reliable profile t...Wind turbine size has increased continuously and correspondingly also its Reynolds numbers. The Reynolds number effect can therefore no longer be ignored in design and optimization of wind turbines. Reliable profile test data should be available. A suitable facility for testing wind turbine profiles at high Reynolds numbers is the Cryogenic Wind Tunnel Cologne DNW-KKK. By means of injecting liquid nitrogen the tunnel can be cooled down to 100 K and the Reynolds number therefore can be raised accordingly. The maximum Reynolds number for 2D profile tests can reach 27x10^6. In this paper the test uncertainty and the flow quality of DNW-KKK were analyzed. Then some test results on the Reynolds number effect of the wind turbine profiles will be presented. The Reynolds number effect is different from model to model. Especially for thick profiles and flow control devices the Reynolds number effect is not always like the description in literature.展开更多
As high-rise cooling towers are constantly emerging,wind effects on this kind of wind-sensitive structures have attracted more and more attention,especially in typhoon prone areas.Terrain Type B turbulent flow fields ...As high-rise cooling towers are constantly emerging,wind effects on this kind of wind-sensitive structures have attracted more and more attention,especially in typhoon prone areas.Terrain Type B turbulent flow fields under the normal wind and typhoon are simulated by active wind tunnel technology,and rigid-pressure-measurement model and aero-elastic-vibration-measurement model of a large cooling tower are built.The stagnation point,peak suction point,separation point and leeward point of the throat position shell are selected to analyze pressure coefficient,probability distribution,peak factor,power spectral density and dynamic amplification factor under normal wind and typhoon.It is clarified that there exists a significant non-Gaussian characteristic under typhoon condition,which also exists in structural response level.Resonance response ratio of the total response is higher during typhoon condition.The maximum value of dynamic amplification coefficient under typhoon field is up to 1.18 times over that under normal wind.The findings of this study are expected to be of interest and practical use to professional and researchers involved in the wind-resistant designs of super-large cooling towers in typhoon prone regions.展开更多
With the increased availability of experimental measurements aiming at probing wind resources and wind turbine operations,machine learning(ML)models are poised to advance our understanding of the physics underpinning ...With the increased availability of experimental measurements aiming at probing wind resources and wind turbine operations,machine learning(ML)models are poised to advance our understanding of the physics underpinning the interaction between the atmospheric boundary layer and wind turbine arrays,the generated wakes and their interactions,and wind energy harvesting.However,the majority of the existing ML models for predicting wind turbine wakes merely recreate Computational fluid dynamics(CFD)simulated data with analogous accuracy but reduced computational costs,thus providing surrogate models rather than enhanced data-enabled physics insights.Although ML-based surrogate models are useful to overcome current limitations associated with the high computational costs of CFD models,using ML to unveil processes from experimental data or enhance modeling capabilities is deemed a potential research direction to pursue.In this letter,we discuss recent achievements in the realm of ML modeling of wind turbine wakes and operations,along with new promising research strategies.展开更多
The non-dominated sorting genetic algorithm （NSGA） is improved with the controlled elitism and dynamic crowding distance. A novel multi-objective optimization algorithm is obtained for wind turbine blades. As an exa...The non-dominated sorting genetic algorithm （NSGA） is improved with the controlled elitism and dynamic crowding distance. A novel multi-objective optimization algorithm is obtained for wind turbine blades. As an example, a 5 MW wind turbine blade design is presented by taking the maximum power coefficient and the minimum blade mass as the optimization objectives. The optimal results show that this algorithm has good performance in handling the multi-objective optimization of wind turbines, and it gives a Pareto-optimal solution set rather than the optimum solutions to the conventional multi objective optimization problems. The wind turbine blade optimization method presented in this paper provides a new and general algorithm for the multi-objective optimization of wind turbines.展开更多
This paper starts with brief introduction to the open topic of the CFD and wing tunnel correlation study, followed by a description of the Chinese Aeronautical Establishment（CAE） –Aerodynamic Validation Model（AVM...This paper starts with brief introduction to the open topic of the CFD and wing tunnel correlation study, followed by a description of the Chinese Aeronautical Establishment（CAE） –Aerodynamic Validation Model（AVM） and its wind tunnel test in the German-Dutch Wind tunnels（DNW）. The features of the aerodynamic design, the CFD approach, the wind tunnel model fabrication and the experimental techniques are discussed along with the motivation of the CAEDNW workshop on CFD-wind tunnel correlation study. The workshop objective is focused on the interference from the aero-elastic deformation of the wind tunnel model and the model support system to the aerodynamic performance and CFD validations. The four study cases, geometry and mesh preparation of the workshop are introduced. A comprehensive summary of the CFD results from the organizer and the participants is provided. Major observations, both CFD to CFD and CFD to wind tunnel, are identified and summarized. The CFD results of the participants are in good agreement with each other, and with the wind tunnel test data when the wing deformation and a Z-sting system are included in the CFD, indicating the importance of considering such interference at high subsonic Mach number of 0.85.展开更多
文摘China wind atlas was made by numerical simulation and the wind energy potential in China was calculated. The model system for wind energy resource assessment was set up based on Canadian Wind Energy Simulating Toolkit (WEST) and the simulating method was as follows. First, the weather classes were obtained depend on meteorological data of 30 years. Then, driven by the initial meteorological field produced by each weather class, the meso-scale model ran for the distribution of wind energy resources according each weather class condition one by one. Finally, averaging all the modeling output weighted by the occurrence frequency of each weather class, the annual mean distribution of wind energy resources was worked out. Compared the simulated wind energy potential with other results from several activities and studies for wind energy resource assessment, it is found that the simulated wind energy potential in mainland of China is 3 times that from the second and the third investigations for wind energy resources by CMA, and is similar to the wind energy potential obtained by NREL in Solar and Wind Energy Resource Assessment(SWERA) project. The simulated offshore wind energy potential of China seems smaller than the true value. According to the simulated results of CMA and considering lots of limited factors to wind energy development, the final conclusion can be obtained that the wind energy availability in China is 700～1 200 GW, in which 600～1 000 GW is in mainland and 100～200 GW is on offshore, and wind power will become the important part of energy composition in future.
文摘Wind energy is a kind of clean renewable energy, which is also relatively mature in technology, with largescale development conditions and prospect for the commercialization. The development of wind energy is a systematic project, involving policy, law, technology, economy, society, environment, education and other aspects. The relationship among all the aspects should be well treated and coordinated. This paper has discussed the following relationships which should be well coordinated: relationship between wind resources and wind energy development, relationship between the wind turbine generator system and the components, relationship between wind energy technology and wind energy industry, relationship between off-grid wind power and grid-connected wind power, relationship between wind farm and the power grid, relationship between onshore wind power and offshore wind power, relationship between wind energy and other energies, relationship between technology introduction and self-innovation, relationship among foreign-funded, joint ventured and domestic-funded enterprises and relationship between the government guidance and the market regulation, as well as giving out some suggestions.
基金This work is supported by the National Key Research and Development Program of China(No.2023YFB4203000)the National Natural Science Foundation of China(No.U22A20178)
文摘Complicated loads encountered by floating offshore wind turbines(FOWTs)in real sea conditions are crucial for future optimization of design,but obtaining data on them directly poses a challenge.To address this issue,we applied machine learning techniques to obtain hydrodynamic and aerodynamic loads of FOWTs by measuring platform motion responses and wave-elevation sequences.First,a computational fluid dynamics(CFD)simulation model of the floating platform was established based on the dynamic fluid body interaction technique and overset grid technology.Then,a long short-term memory(LSTM)neural network model was constructed and trained to learn the nonlinear relationship between the waves,platform-motion inputs,and hydrodynamic-load outputs.The optimal model was determined after analyzing the sensitivity of parameters such as sample characteristics,network layers,and neuron numbers.Subsequently,the effectiveness of the hydrodynamic load model was validated under different simulation conditions,and the aerodynamic load calculation was completed based on the D'Alembert principle.Finally,we built a hybrid-scale FOWT model,based on the software in the loop strategy,in which the wind turbine was replaced by an actuation system.Model tests were carried out in a wave basin and the results demonstrated that the root mean square errors of the hydrodynamic and aerodynamic load measurements were 4.20%and 10.68%,respectively.
基金primarily supported by the National Key R&D Program of China[grant number 2021YFC3000904]the Jiangsu Provincial Key Technology R&D Program[grant number BE2022851]National Natural Science Foundation of China[grant number 42405035]。
文摘Vector winds play a crucial role in weather and climate,as well as the effective utilization of wind energy resources.However,limited research has been conducted on treating the wind field as a vector field in the evaluation of numerical weather prediction models.In this study,the authors treat vector winds as a whole by employing a vector field evaluation method,and evaluate the mesoscale model of the China Meteorological Administration(CMA-MESO)and ECMWF forecast,with reference to ERA5 reanalysis,in terms of multiple aspects of vector winds over eastern China in 2022.The results show that the ECMWF forecast is superior to CMA-MESO in predicting the spatial distribution and intensity of 10-m vector winds.Both models overestimate the wind speed in East China,and CMA-MESO overestimates the wind speed to a greater extent.The forecasting skill of the vector wind field in both models decreases with increasing lead time.The forecasting skill of CMA-MESO fluctuates more and decreases faster than that of the ECMWF forecast.There is a significant negative correlation between the model vector wind forecasting skill and terrain height.This study provides a scientific evaluation of the local application of vector wind forecasts of the CMA-MESO model and ECMWF forecast.
基金Supported by Research on Key Technologies of Lightning Intelligent Protection System for Guangdong Energy Hehe Sea Wind Farm(SFC/QZW-ZX-XF-24-020).
文摘In the past,the lightning strike risk assessment of wind farms mainly referred to the Lightning Protection Part 2:Risk Management(IEC 62305-2-2010)and the Lightning Protection of Wind Energy System(IEC 61400-24-2019)based on protection angle method.In fact,the basic idea of the two is the same,that is,the source of the lightning fan is replaced by S1-S4 of the former lightning building with the latter ND-NDJ.According to the above method of wind farm evaluation,it has been proved that the practice can not achieve good results.Taking offshore wind farm as an example,this paper introduces a new method of establishing six evaluation indicators to determine the risk level according to the new technology and compliance principle of regional lightning protection(semi-circular method),which can be used for reference by wind farm technicians.
基金funded by“The Factors Affecting the Accuracy of Wind Resource Assessment and Comprehensive Post-Evaluation Techniques for Operating Wind Power Projects,”grant number YJ24.002“The Research and Application of Future Medium to Long Term Wind Resource Assessment for Wind Farms Based on Artificial Intelligence Project,”grant number 2023021。
文摘Improving the accuracy of the evaluation of the performance of wind farms in large wind power bases located in complex terrain under the actual atmosphere is crucial to the sustainable development of wind power.To this end,this study combined the Weather Research and Forecasting(WRF)model with the Wind Farm Parameterization(WFP)method to investigate the wake characteristics and operational performance of large onshore wind farms in the complex terrain of Jiuquan City,Gansu Province,China.The research results showed that after verification,the systematic error of the WRF simulations was less than 3%.The WRF model and the WFP scheme simulated a significant warming phenomenon within the wind power base area,while a cooling effect was observed outside.The analysis of the wake effects indicated that the impact of PhaseⅠconstruction on PhaseⅡconstruction of the wind power base was minimal.During the operation of the entire wind power base,the wind speed within the wind farm decreased by approximately 10%,and the influence range of the predominant wind direction extended over a hundred kilometers downwind.The research conclusions provide a powerful scientific basis for optimizing design and operation,improving efficiency,minimizing the negative impacts on adjacent wind turbines,and ensuring the sustainable development of wind energy through dynamic planning and scientific assessment.
基金the National Natural Science Foundation of China(Grant Nos.52276197, 52166014)Gansu Province Key Research and Development Program—Industrial Project(Grant No.23YFGA0069).
文摘A downburst is a strong downdraft generated by intense thunderstorm clouds,producing radially divergent and highly destructive winds near the ground.Its characteristic scales are expressed through random variations in jet height,velocity,and diameter during an event.In this study,a reduced-scale parked wind turbine is exposed to downburst wind fields to investigate the resulting extreme wind loads.The analysis emphasizes both the flow structure of downbursts and the variations of surface wind pressure on turbine blades under different jet parameters.Results show that increasing jet velocity markedly enhances the maximum horizontal wind speed,while greater jet height reduces the horizontal wind speed and shifts the peak velocity closer to the jet center.Increasing jet diameter primarily affects the radial position of the maximum horizontal wind speed.For the wind turbine,the maximum equivalent stress and blade displacement increase almost linearly with jet velocity,but exhibit the opposite trend with jet diameter.Specifically,as jet velocity rises from 10 m/s to 20 m/s,the surface pressure coefficient at the blade tip increases by approximately 4.5 times.Changes in jet diameter indirectly alter the turbine’s relative position within the wind field,leading to variations in wind load direction and exposure area.Conversely,increasing jet height extends the dissipation path of the downdraft,thereby reducing the intensity of the airflow acting on the blades.For example,when jet height increases from 0.3 m to 1.2 m,the surface pressure coefficient at the blade tip decreases by nearly 50%.
基金Project supported by the National Natural Science Foundation of China (No. 50808148)the National Key Technology R&D Program (No. 2008BAG07B02), China
文摘In order to investigate the wind characteristics of coastal areas of China, a long-term field measurement of natural wind was carried out. Based on the field measurement results, this paper presents the natural wind characteristics of typhoons and strong monsoons at the site of Xi-hou-men Bridge, including mean wind speed, mean wind direction, mean wind elevation angle, turbulent intensity, gust factor, turbulence integral length scales, power spectrum of wind speed and spatial correlation of gusty wind, the profiles of mean wind speed and turbulent intensity, etc. The correlation among wind characteristics is analyzed in detail, and the similarities and differences of wind characteristics between typhoons and monsoons are analyzed. These results can pro- vide detailed wind characteristics of coastal areas of China.
基金supported by a Horizontal Project on the Development of a Hybrid Energy Storage Simulation Model for Wind Power Based on an RT-LAB Simulation System(PH2023000190)the Inner Mongolia Natural Science Foundation Project and the Optimization of Exergy Efficiency of a Hybrid Energy Storage System with Crossover Control for Wind Power(2023JQ04).
文摘Present of wind power is sporadically and cannot be utilized as the only fundamental load of energy sources.This paper proposes a wind-solar hybrid energy storage system(HESS)to ensure a stable supply grid for a longer period.A multi-objective genetic algorithm(MOGA)and state of charge(SOC)region division for the batteries are introduced to solve the objective function and configuration of the system capacity,respectively.MATLAB/Simulink was used for simulation test.The optimization results show that for a 0.5 MW wind power and 0.5 MW photovoltaic system,with a combination of a 300 Ah lithium battery,a 200 Ah lead-acid battery,and a water storage tank,the proposed strategy reduces the system construction cost by approximately 18,000 yuan.Additionally,the cycle count of the electrochemical energy storage systemincreases from4515 to 4660,while the depth of discharge decreases from 55.37%to 53.65%,achieving shallow charging and discharging,thereby extending battery life and reducing grid voltage fluctuations significantly.The proposed strategy is a guide for stabilizing the grid connection of wind and solar power generation,capability allocation,and energy management of energy conservation systems.
文摘This paper presents an analysis of a pre-feasibility study of a 10 MW offshore wind power project in Nakhon Si Thammarat province, southern Thailand. The wind speeds at the hub heights of large scale wind turbine generators （WTG）, i.e. 80-100 m, were extrapolated using monthly mean wind shear coefficients and the l/7th exponent. Using WAsP 9.0, the annual energy production from several models of offshore wind farms using different WTG was analyzed. The capacity factor and the cost of energy were then computed. Using best available estimates, the analysis shows that the estimated annual mean offshore wind speeds at 80-100 m were in the range of 6.4 and 8.3 m/s. The annual energy production by the wind farm from nine models of wind turbine generators were in the range of 20-39 GWh/year, corresponding to a capacity factor in the range of 26-46%, while the cost of energy was 12-15 US cent/kWh.
基金Projects(50978203,51208254)supported by the National Natural Science Foundation of ChinaProject(BK2012390)supported by Natural Science Foundation of Jiangsu Province,ChinaProject supported by the Priority Academic Program Development of Jiangsu Higher Education Institutions,China
文摘Traditional gust load factor(GLF)method,inertial wind load(IWL)method and tri-component method(LRC+IWL)cannot accurately analyze the wind-induced responses of super-large cooling towers,so the real combination formulas of fluctuating wind-induced responses and equivalent static wind loads(ESWLSs)were derived based on structural dynamics and random vibration theory.The consistent coupled method(CCM)was presented to compensate the coupled term between background and resonant response.Taking the super-large cooling tower(H=215 m)of nuclear power plant in Jiangxi Province,China,which is the highest and largest in China,as the example,based on modified equivalent beam-net design method,the aero-elastic model for simultaneous pressure and vibration measurement of super-large cooling tower is firstly carried out.Then,combining wind tunnel test and CCM,the effects of self-excited force on the surface pressures and wind-induced responses are discussed,and the wind-induced response characteristics of background component,resonant component,coupled term between background and resonant response,fluctuating responses,and wind vibration coefficients are discussed.It can be concluded that wind-induced response mechanism must be understood to direct the wind resistant design for super-large cooling towers.
基金Projects(51778544,51978589,51908472) supported by the National Natural Science Foundation of ChinaProject(2682021CG014) supported by the Fundamental Research Funds for the Central Universities,China。
文摘Two trains passing each other is controlling factor for the wind-vehicle-bridge systems.To test the aerodynamic characteristics of moving vehicles under crosswinds when two trains are passing each other,a wind tunnel test device,which has two moving tracks,was developed.The rationality of the test result was discussed,the effects of intersection mode,yaw angle and lane spacing on the aerodynamic coefficients of the leeward train were analyzed,and the difference of aerodynamic coefficients between the head vehicle and the tail vehicle was discussed.The results show that the proposed test device has good repeatability.The intersection modes have a certain effect on the aerodynamic force of the leeward train when two trains are passing each other,and the results should be more reasonable during the two trains dynamic passing each other.With the decrease of yaw angle,the sudden change of train aerodynamic coefficients is more obvious.The decrease of lane spacing will increase the sudden change of leeward vehicles.In the process of two trains passing each other,the aerodynamic coefficients of the head vehicle and tail vehicle are significantly different,so the coupling vibration analysis of wind-vehicle-bridge system should be considered separately.
基金Project supported by the National Basic Research Program of China(No.2014CB046201)the National Natural Science Foundation of China(Nos.51766009 and 51566011)
文摘Under natural conditions, wind turbines are inevitably eroded by the action of sand-wind flow. To further investigate the effects of dust drift on the erosion of the wind turbine blades in sand-wind environments~ the effects of the wind velocity, particle diameter, and particle density on the erosion of wind turbine airfoils are studied, and the effects of the particle Stokes number on the airfoil erosion are discussed. The results show that, when the angle of attack （AOA） is 6.1~, there will be no erosion on the airfoil surface if the particle Stokes number is lower than 0.013 5, whereas erosion will occur if the particle Stokes number is higher than 0.015 1. Therefore, there exists a critical range for the particle Stokes number. When the particle Stokes number is higher than the maximum value in the critical range, airfoil erosion will occur. The result is further confirmed by changing the particle diameter, particle density, and inflow speed. It is shown that the erosion area on the airfoil and the maximum erosion rate are almost equal under the same particle Stokes number and AOA. The extent of airfoil erosion increases when the particle Stokes number increases, and the critical particle Stokes number increases when the AOA increases. Moreover, the geometric shape of the airfoil pressure surface greatly affects the airfoil erosion, especially at the curvature near the leading edge.
基金Scientific Research Projects Unit of Erciyes University under the contract numbers:FDK-2019-8616 and FDK-2025-14774(https://bap.erciyes.edu.tr/,accessed on 12 October 2025)The Scientific and Technological Research Council of Turkey(TUB˙ITAK)for the Doctoral Scholarship for Priority Areas 2211/C for Ramazan OZKAN(https://tubitak.gov.tr,accessed on 12 October 2025).
文摘The optimization of turbine blades is crucial in improving the efficiency of wind energy systems and developing clean energy production models.This paper presented a novel approach to the structural design of smallscale turbine blades using the Artificial Bee Colony(ABC)Algorithm based on the stochastic method to optimize both mass and cost(objective functions).The study used computational fluid dynamics(CFD)and structural analysis to consider the fluid-structure interaction.The optimization algorithm defined several variables:structural constraints,the type of composite material,and the number of composite layers to form a mathematical model.The numerical modeling was performed using the Ansys Fluent software and its Fluid-Structure Interaction(FSI)module.The ANSYS Composite PrePost(ACP)advanced composite modeling method was utilized in the structural design of composite materials.This study showed that the structurally optimized small-scale turbine blades provided a sustainable solution with improved efficiency compared to traditional designs.Furthermore,using CFD,structural analysis,and material characterization techniques first considered in this study highlights the importance of considering structural behavior when optimizing turbine blade designs.
文摘Wind turbine size has increased continuously and correspondingly also its Reynolds numbers. The Reynolds number effect can therefore no longer be ignored in design and optimization of wind turbines. Reliable profile test data should be available. A suitable facility for testing wind turbine profiles at high Reynolds numbers is the Cryogenic Wind Tunnel Cologne DNW-KKK. By means of injecting liquid nitrogen the tunnel can be cooled down to 100 K and the Reynolds number therefore can be raised accordingly. The maximum Reynolds number for 2D profile tests can reach 27x10^6. In this paper the test uncertainty and the flow quality of DNW-KKK were analyzed. Then some test results on the Reynolds number effect of the wind turbine profiles will be presented. The Reynolds number effect is different from model to model. Especially for thick profiles and flow control devices the Reynolds number effect is not always like the description in literature.
基金supported by the National Key Research and Development Program of China (Nos. 2018YFC0809600,2018YFC0809604)the National Natural Science Foundation of China(No.51678451).
文摘As high-rise cooling towers are constantly emerging,wind effects on this kind of wind-sensitive structures have attracted more and more attention,especially in typhoon prone areas.Terrain Type B turbulent flow fields under the normal wind and typhoon are simulated by active wind tunnel technology,and rigid-pressure-measurement model and aero-elastic-vibration-measurement model of a large cooling tower are built.The stagnation point,peak suction point,separation point and leeward point of the throat position shell are selected to analyze pressure coefficient,probability distribution,peak factor,power spectral density and dynamic amplification factor under normal wind and typhoon.It is clarified that there exists a significant non-Gaussian characteristic under typhoon condition,which also exists in structural response level.Resonance response ratio of the total response is higher during typhoon condition.The maximum value of dynamic amplification coefficient under typhoon field is up to 1.18 times over that under normal wind.The findings of this study are expected to be of interest and practical use to professional and researchers involved in the wind-resistant designs of super-large cooling towers in typhoon prone regions.
基金supported by the National Science Foundation(NSF)CBET,Fluid Dynamics CAREER program(Grant No.2046160),program manager Ron Joslin.
文摘With the increased availability of experimental measurements aiming at probing wind resources and wind turbine operations,machine learning(ML)models are poised to advance our understanding of the physics underpinning the interaction between the atmospheric boundary layer and wind turbine arrays,the generated wakes and their interactions,and wind energy harvesting.However,the majority of the existing ML models for predicting wind turbine wakes merely recreate Computational fluid dynamics(CFD)simulated data with analogous accuracy but reduced computational costs,thus providing surrogate models rather than enhanced data-enabled physics insights.Although ML-based surrogate models are useful to overcome current limitations associated with the high computational costs of CFD models,using ML to unveil processes from experimental data or enhance modeling capabilities is deemed a potential research direction to pursue.In this letter,we discuss recent achievements in the realm of ML modeling of wind turbine wakes and operations,along with new promising research strategies.
基金Project supported by the National Basic Research Program of China (973 Program) (No. 2007CB714600)
文摘The non-dominated sorting genetic algorithm （NSGA） is improved with the controlled elitism and dynamic crowding distance. A novel multi-objective optimization algorithm is obtained for wind turbine blades. As an example, a 5 MW wind turbine blade design is presented by taking the maximum power coefficient and the minimum blade mass as the optimization objectives. The optimal results show that this algorithm has good performance in handling the multi-objective optimization of wind turbines, and it gives a Pareto-optimal solution set rather than the optimum solutions to the conventional multi objective optimization problems. The wind turbine blade optimization method presented in this paper provides a new and general algorithm for the multi-objective optimization of wind turbines.
文摘This paper starts with brief introduction to the open topic of the CFD and wing tunnel correlation study, followed by a description of the Chinese Aeronautical Establishment（CAE） –Aerodynamic Validation Model（AVM） and its wind tunnel test in the German-Dutch Wind tunnels（DNW）. The features of the aerodynamic design, the CFD approach, the wind tunnel model fabrication and the experimental techniques are discussed along with the motivation of the CAEDNW workshop on CFD-wind tunnel correlation study. The workshop objective is focused on the interference from the aero-elastic deformation of the wind tunnel model and the model support system to the aerodynamic performance and CFD validations. The four study cases, geometry and mesh preparation of the workshop are introduced. A comprehensive summary of the CFD results from the organizer and the participants is provided. Major observations, both CFD to CFD and CFD to wind tunnel, are identified and summarized. The CFD results of the participants are in good agreement with each other, and with the wind tunnel test data when the wing deformation and a Z-sting system are included in the CFD, indicating the importance of considering such interference at high subsonic Mach number of 0.85.
