Pub Date : 2024-11-07DOI: 10.1016/j.jweia.2024.105932
Juan A. Cárdenas-Rondón , Omar Gómez-Ortega , Carlos Rodríguez-Casado , Mikel Ogueta-Gutiérrez , Sebastián Franchini
Based on the experimental data of the aerodynamic derivative presented in the literature, evidence was found that supports the existence of a similarity solution between , the effective mean angle of attack, , the tracker height-to-width ratio, , and the reduced velocity. . With this similarity solution, it is possible to estimate for any and with a significantly reduced amount of experimental data. This represents a notable advancement compared to the current state of the art, as it could allow for a more detailed analysis of aeroelastic instability in flat solar trackers with fewer experimental requirements. This article presents the developed formulation and the process followed to obtain the discovered similarity solution. Relying on the similarity solution, a simplified model of has been proposed as a function of the reduced velocity and for .
{"title":"Similarity solution for sectional A2∗ aerodynamic derivative for single axis solar trackers at various angles of attack and ground distances","authors":"Juan A. Cárdenas-Rondón , Omar Gómez-Ortega , Carlos Rodríguez-Casado , Mikel Ogueta-Gutiérrez , Sebastián Franchini","doi":"10.1016/j.jweia.2024.105932","DOIUrl":"10.1016/j.jweia.2024.105932","url":null,"abstract":"<div><div>Based on the experimental data of the aerodynamic derivative <span><math><msubsup><mrow><mi>A</mi></mrow><mrow><mn>2</mn></mrow><mrow><mo>∗</mo></mrow></msubsup></math></span> presented in the literature, evidence was found that supports the existence of a similarity solution between <span><math><msubsup><mrow><mi>A</mi></mrow><mrow><mn>2</mn></mrow><mrow><mo>∗</mo></mrow></msubsup></math></span>, the effective mean angle of attack, <span><math><msubsup><mrow><mi>α</mi></mrow><mrow><mi>m</mi><mi>e</mi><mi>a</mi><mi>n</mi></mrow><mrow><mi>e</mi><mi>f</mi><mi>f</mi></mrow></msubsup></math></span>, the tracker height-to-width ratio, <span><math><mrow><mi>H</mi><mo>/</mo><mi>B</mi></mrow></math></span>, and the reduced velocity. <span><math><msub><mrow><mi>U</mi></mrow><mrow><mi>r</mi></mrow></msub></math></span>. With this similarity solution, it is possible to estimate <span><math><msubsup><mrow><mi>A</mi></mrow><mrow><mn>2</mn></mrow><mrow><mo>∗</mo></mrow></msubsup></math></span> for any <span><math><mrow><msubsup><mrow><mi>α</mi></mrow><mrow><mi>m</mi><mi>e</mi><mi>a</mi><mi>n</mi></mrow><mrow><mi>e</mi><mi>f</mi><mi>f</mi></mrow></msubsup><mo>∈</mo><mfenced><mrow><mo>−</mo><mn>40</mn><mo>°</mo><mo>,</mo><mo>+</mo><mn>40</mn><mo>°</mo></mrow></mfenced></mrow></math></span> and <span><math><mrow><mi>H</mi><mo>/</mo><mi>B</mi><mo>∈</mo><mfenced><mrow><mn>0</mn><mo>.</mo><mn>3</mn><mo>,</mo><mn>2</mn><mo>.</mo><mn>0</mn></mrow></mfenced></mrow></math></span> with a significantly reduced amount of experimental data. This represents a notable advancement compared to the current state of the art, as it could allow for a more detailed analysis of aeroelastic instability in flat solar trackers with fewer experimental requirements. This article presents the developed formulation and the process followed to obtain the discovered similarity solution. Relying on the similarity solution, a simplified model of <span><math><msubsup><mrow><mi>A</mi></mrow><mrow><mn>2</mn></mrow><mrow><mo>∗</mo></mrow></msubsup></math></span> has been proposed as a function of the reduced velocity and <span><math><mrow><mi>H</mi><mo>/</mo><mi>B</mi></mrow></math></span> for <span><math><mrow><msubsup><mrow><mi>α</mi></mrow><mrow><mi>m</mi><mi>e</mi><mi>a</mi><mi>n</mi></mrow><mrow><mi>e</mi><mi>f</mi><mi>f</mi></mrow></msubsup><mo>=</mo><mn>0</mn><mo>°</mo></mrow></math></span>.</div></div>","PeriodicalId":54752,"journal":{"name":"Journal of Wind Engineering and Industrial Aerodynamics","volume":"255 ","pages":"Article 105932"},"PeriodicalIF":4.2,"publicationDate":"2024-11-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142660458","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Multiple hazards caused by tropical cyclones (TCs), such as heavy rains and strong winds, result in substantial property losses and casualties worldwide each year. TC wind field models, describing the development of the wind hazard, are key within early warning realizations and associated risk assessments. Different to conventional parametric, analytical or meteorological numerical models, this study aims to develop a machine-learning-based approach for modeling TC wind fields by incorporating multiple meteorological parameters. The wind field model considers linear and nonlinear modeling respectively, where the input data includes various meteorological parameters such as surface pressure gradient (SPG), geopotential (GEO), boundary layer height (BLH), and forecast surface roughness (FSR). The output data is the TC wind field data of the Regional and Mesoscale Meteorology Branch (RAMMB) extracted by image recognition method, and assimilated with the wind field from the fifth generation of the European Center for Medium-Range Weather Forecasts (ECMWF) atmospheric reanalysis dataset ERA5. In the linear model, various combinations of parameters are considered, yet always yielding unsatisfactory results. The best results in the linear model were obtained using all four parameter combinations, where the root mean square error (RMSE) was 2.60 m/s and the coefficient of determination value was 0.44. To increase performance, three nonlinear machine learning methods—Fully Connected Deep Neural Networks (FC-DNN), Convolutional Neural Networks (CNN), and Transformer—are introduced to the training process. Comparing the wind field continuity, RMSE and between the three models, it is found that the Transformer outperforms all other models, with value of 0.877 and an RMSE of 2.23. As a final step, the trained Transformer model was used to predict the evolution of wind speed of the Typhoon Lekima (1909), in what could serve as effective model validation.
{"title":"Machine-learning-based tropical cyclone wind field model incorporating multiple meteorological parameters","authors":"Miaomiao Wei , Genshen Fang , Nikolaos Nikitas , Yaojun Ge","doi":"10.1016/j.jweia.2024.105936","DOIUrl":"10.1016/j.jweia.2024.105936","url":null,"abstract":"<div><div>Multiple hazards caused by tropical cyclones (TCs), such as heavy rains and strong winds, result in substantial property losses and casualties worldwide each year. TC wind field models, describing the development of the wind hazard, are key within early warning realizations and associated risk assessments. Different to conventional parametric, analytical or meteorological numerical models, this study aims to develop a machine-learning-based approach for modeling TC wind fields by incorporating multiple meteorological parameters. The wind field model considers linear and nonlinear modeling respectively, where the input data includes various meteorological parameters such as surface pressure gradient (SPG), geopotential (GEO), boundary layer height (BLH), and forecast surface roughness (FSR). The output data is the TC wind field data of the Regional and Mesoscale Meteorology Branch (RAMMB) extracted by image recognition method, and assimilated with the wind field from the fifth generation of the European Center for Medium-Range Weather Forecasts (ECMWF) atmospheric reanalysis dataset ERA5. In the linear model, various combinations of parameters are considered, yet always yielding unsatisfactory results. The best results in the linear model were obtained using all four parameter combinations, where the root mean square error (RMSE) was 2.60 m/s and the coefficient of determination <span><math><mrow><msup><mi>R</mi><mn>2</mn></msup></mrow></math></span> value was 0.44. To increase performance, three nonlinear machine learning methods—Fully Connected Deep Neural Networks (FC-DNN), Convolutional Neural Networks (CNN), and Transformer—are introduced to the training process. Comparing the wind field continuity, RMSE and <span><math><mrow><msup><mi>R</mi><mn>2</mn></msup></mrow></math></span> between the three models, it is found that the Transformer outperforms all other models, with <span><math><mrow><msup><mi>R</mi><mn>2</mn></msup></mrow></math></span> value of 0.877 and an RMSE of 2.23. As a final step, the trained Transformer model was used to predict the evolution of wind speed of the Typhoon Lekima (1909), in what could serve as effective model validation.</div></div>","PeriodicalId":54752,"journal":{"name":"Journal of Wind Engineering and Industrial Aerodynamics","volume":"255 ","pages":"Article 105936"},"PeriodicalIF":4.2,"publicationDate":"2024-11-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142578652","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-10-29DOI: 10.1016/j.jweia.2024.105935
Binbin Yao , Zhisong Wang , Zhiyuan Fang , Zhengliang Li
Downbursts, as a strong localized wind event, have caused significant damage to engineering structures throughout the world. However, given the spatial and temporal randomness of such strong winds, on-site measurements are often difficult to obtain a sufficient amount of valid wind field information in a short period of time. To refine the resolution of the wind field, this study proposes a physics-informed neural network network-based (PINN-based) approach to reconstruct the downburst from limited observed data. The Navier-Stokes (N-S) equations are embedded into the fully connected neural network as a physical constraint to construct the PINN. The PINN model is then validated by the reconstruction of numerical downburst generated by large eddy simulations. The reconstruction of the sparse downburst wind field by PINN performs well in both interpolation and extrapolation prediction. The optimal construction of the PINN has been evaluated through parameter analysis of the influence of training data and network parameters. Finally, the optimal PINN construction is used to reconstruct the wind field of the experimental data with a relative error of 5% for the horizontal wind velocity.
{"title":"Reconstruction of downburst wind fields using physics-informed neural network","authors":"Binbin Yao , Zhisong Wang , Zhiyuan Fang , Zhengliang Li","doi":"10.1016/j.jweia.2024.105935","DOIUrl":"10.1016/j.jweia.2024.105935","url":null,"abstract":"<div><div>Downbursts, as a strong localized wind event, have caused significant damage to engineering structures throughout the world. However, given the spatial and temporal randomness of such strong winds, on-site measurements are often difficult to obtain a sufficient amount of valid wind field information in a short period of time. To refine the resolution of the wind field, this study proposes a physics-informed neural network network-based (PINN-based) approach to reconstruct the downburst from limited observed data. The Navier-Stokes (N-S) equations are embedded into the fully connected neural network as a physical constraint to construct the PINN. The PINN model is then validated by the reconstruction of numerical downburst generated by large eddy simulations. The reconstruction of the sparse downburst wind field by PINN performs well in both interpolation and extrapolation prediction. The optimal construction of the PINN has been evaluated through parameter analysis of the influence of training data and network parameters. Finally, the optimal PINN construction is used to reconstruct the wind field of the experimental data with a relative error of 5% for the horizontal wind velocity.</div></div>","PeriodicalId":54752,"journal":{"name":"Journal of Wind Engineering and Industrial Aerodynamics","volume":"254 ","pages":"Article 105935"},"PeriodicalIF":4.2,"publicationDate":"2024-10-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142538414","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The univariate design method may not match the wind resistance demands of bridges in mountainous areas. Therefore, it is crucial to comprehensively consider the joint effect of multiple wind parameters for determining wind-resistant design parameters of bridges. To address challenges such as short measurement periods and difficulties in expanding the extreme value model of wind parameters, a Bootstrap resampling strategy incorporating seasonal wind speed trends was developed, verified, and applied to long-term probabilistic modeling; thus, the uncertainty of the probability model of average wind parameters was investigated. Then, taking the environmental contour of wind speed and attack angle under varying wind directions as the basis, a technical framework for wind-resistant bridges based on multi-parameter joint design is proposed. Meanwhile, the main girder's longitudinal and lateral design wind speeds are derived under the joint influence of attack angle and yaw angle. The results show that the control wind direction of longitudinal and lateral design wind speed is different. The joint design considering multiple wind parameters effectively makes up the limitations of traditional methods. It provides valuable insights for wind-resistant design and lifecycle toughness evaluation of bridges in mountainous areas.
{"title":"Study on joint design method of multiple wind parameters for long-span bridges in deep-cutting gorge areas based on field measurement","authors":"Jinxiang Zhang , Fanying Jiang , Mingjin Zhang , Haoxiang Zheng , Yongle Li , Junsong Liang","doi":"10.1016/j.jweia.2024.105930","DOIUrl":"10.1016/j.jweia.2024.105930","url":null,"abstract":"<div><div>The univariate design method may not match the wind resistance demands of bridges in mountainous areas. Therefore, it is crucial to comprehensively consider the joint effect of multiple wind parameters for determining wind-resistant design parameters of bridges. To address challenges such as short measurement periods and difficulties in expanding the extreme value model of wind parameters, a Bootstrap resampling strategy incorporating seasonal wind speed trends was developed, verified, and applied to long-term probabilistic modeling; thus, the uncertainty of the probability model of average wind parameters was investigated. Then, taking the environmental contour of wind speed and attack angle under varying wind directions as the basis, a technical framework for wind-resistant bridges based on multi-parameter joint design is proposed. Meanwhile, the main girder's longitudinal and lateral design wind speeds are derived under the joint influence of attack angle and yaw angle. The results show that the control wind direction of longitudinal and lateral design wind speed is different. The joint design considering multiple wind parameters effectively makes up the limitations of traditional methods. It provides valuable insights for wind-resistant design and lifecycle toughness evaluation of bridges in mountainous areas.</div></div>","PeriodicalId":54752,"journal":{"name":"Journal of Wind Engineering and Industrial Aerodynamics","volume":"254 ","pages":"Article 105930"},"PeriodicalIF":4.2,"publicationDate":"2024-10-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142538413","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-10-29DOI: 10.1016/j.jweia.2024.105929
Lizhi Wen , Kazuyoshi Nishijima
Plate-type debris is a typical type of windborne debris, often originating from roof tiles and shingles. Numerical simulation using aerodynamic models provides a practical method to predict trajectories of windborne debris. In this paper, we first propose a revised model for the 3-degree-of-freedom (3-DOF) flight motion of square plates in winds by integrating experimental data from previous studies. Thereby, we divide the aerodynamic force and moment into a translational part and a rotational part. In addition, we propose conditions of autorotation in the revised model. The calculation of the rotational force and moment depends on whether these conditions are fulfilled. The revised model is validated by comparing the numerical results with experimental results of plate trajectories. Next, based on the revised model for the 3-DOF motion, we propose an aerodynamic model for the 6-DOF motion by incorporating the findings about the rotational force and moment, which were obtained from the authors’ previous study on the 6-DOF motion of square plates. Based on these findings, the model is developed in the way that the direction of the rotational force depends on the relative wind velocity and the angular velocity of plate, and the direction of the rotational moment depends on the translational moment. By doing so the proposed model in this paper avoids directly using a database of aerodynamics, which is large and difficult to obtain. Validation using the experimental results of plate trajectories shows that the proposed model, which has a relatively simple form, performs generally well.
{"title":"An aerodynamic model for 6-DOF flight motion of windborne debris of square plates","authors":"Lizhi Wen , Kazuyoshi Nishijima","doi":"10.1016/j.jweia.2024.105929","DOIUrl":"10.1016/j.jweia.2024.105929","url":null,"abstract":"<div><div>Plate-type debris is a typical type of windborne debris, often originating from roof tiles and shingles. Numerical simulation using aerodynamic models provides a practical method to predict trajectories of windborne debris. In this paper, we first propose a revised model for the 3-degree-of-freedom (3-DOF) flight motion of square plates in winds by integrating experimental data from previous studies. Thereby, we divide the aerodynamic force and moment into a translational part and a rotational part. In addition, we propose conditions of autorotation in the revised model. The calculation of the rotational force and moment depends on whether these conditions are fulfilled. The revised model is validated by comparing the numerical results with experimental results of plate trajectories. Next, based on the revised model for the 3-DOF motion, we propose an aerodynamic model for the 6-DOF motion by incorporating the findings about the rotational force and moment, which were obtained from the authors’ previous study on the 6-DOF motion of square plates. Based on these findings, the model is developed in the way that the direction of the rotational force depends on the relative wind velocity and the angular velocity of plate, and the direction of the rotational moment depends on the translational moment. By doing so the proposed model in this paper avoids directly using a database of aerodynamics, which is large and difficult to obtain. Validation using the experimental results of plate trajectories shows that the proposed model, which has a relatively simple form, performs generally well.</div></div>","PeriodicalId":54752,"journal":{"name":"Journal of Wind Engineering and Industrial Aerodynamics","volume":"254 ","pages":"Article 105929"},"PeriodicalIF":4.2,"publicationDate":"2024-10-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142538412","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Comprehending the wind characteristics in urban environments is crucial to ensure optimal performance and structural integrity of wind turbines operating in urban areas. This study aims to provide a deeper insight into wind characteristics over high-rise buildings rooftop. The impact of a high-rise building configuration on the turbulent wind field characteristics is analyzed, by means of large eddy simulations of a reference wind tunnel experiment. Special attention is paid to the analysis of the second order statistics of the turbulent velocity components, as they are crucial inputs for generating synthetic urban wind fields for wind turbine aeroelastic simulations. A Spectral Representation Method is applied to generate the desired turbulent inflow represented in the experiment study. The correspondence between the predicted statistics and the experimental values of the velocity components over the rooftop reinforces the idea about the practical viability of large eddy simulation to provide atmospheric turbulence information in the urban environment required to characterize the behavior of wind systems operating in that environment. Additionally, the two-points two-times second order statistics are significantly affected by the presence of the high-rise building, especially when those statistics involve at least a point within the recirculation bubble region.
{"title":"Large eddy simulation of the flow around a high-rise building with special focus on the two-points two-times second order statistics of the velocity field","authors":"Mohanad Elagamy , Nishchay Tiwari , Cristobal Gallego-Castillo , Alvaro Cuerva-Tejero , Oscar Lopez-Garcia , Sergio Avila-Sanchez","doi":"10.1016/j.jweia.2024.105914","DOIUrl":"10.1016/j.jweia.2024.105914","url":null,"abstract":"<div><div>Comprehending the wind characteristics in urban environments is crucial to ensure optimal performance and structural integrity of wind turbines operating in urban areas. This study aims to provide a deeper insight into wind characteristics over high-rise buildings rooftop. The impact of a high-rise building configuration on the turbulent wind field characteristics is analyzed, by means of large eddy simulations of a reference wind tunnel experiment. Special attention is paid to the analysis of the second order statistics of the turbulent velocity components, as they are crucial inputs for generating synthetic urban wind fields for wind turbine aeroelastic simulations. A Spectral Representation Method is applied to generate the desired turbulent inflow represented in the experiment study. The correspondence between the predicted statistics and the experimental values of the velocity components over the rooftop reinforces the idea about the practical viability of large eddy simulation to provide atmospheric turbulence information in the urban environment required to characterize the behavior of wind systems operating in that environment. Additionally, the two-points two-times second order statistics are significantly affected by the presence of the high-rise building, especially when those statistics involve at least a point within the recirculation bubble region.</div></div>","PeriodicalId":54752,"journal":{"name":"Journal of Wind Engineering and Industrial Aerodynamics","volume":"254 ","pages":"Article 105914"},"PeriodicalIF":4.2,"publicationDate":"2024-10-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142534108","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-10-25DOI: 10.1016/j.jweia.2024.105934
Feng Hu , Junyi He , Zhifei Liu , Qiusheng Li , Pak-Wai Chan
In this paper, 17 severe typhoons that have affected Hong Kong are simulated using an advanced numerical atmospheric simulation system - Weather Research and Forecasting model (WRF). The simulated surface pressure and wind fields of these typhoons are validated against a wide range of field observations. Then azimuth-dependent models for the radius of maximum winds and the Holland parameter are established statistically at the surface level. It is observed that the shape parameter of the Holland pressure model is smaller at the surface than that at the gradient level. And the Holland wind field model cannot well reproduce the simulated radial wind profiles due to the complexities of nonuniform surface conditions and typhoon dynamics. It is found that the modified Rankine model provides satisfactory estimates of typhoon wind speeds in Hong Kong. Additionally, wind field asymmetries of typhoons approaching Hong Kong are highly correlated with the typhoon track velocity, vertical wind shear and the angle between them. The proposed statistical models and identified characteristics of wind field asymmetries of typhoons will provide useful information for rapidly assessing typhoon wind hazards.
{"title":"Characterizing surface pressure and wind fields of typhoons approaching Hong Kong","authors":"Feng Hu , Junyi He , Zhifei Liu , Qiusheng Li , Pak-Wai Chan","doi":"10.1016/j.jweia.2024.105934","DOIUrl":"10.1016/j.jweia.2024.105934","url":null,"abstract":"<div><div>In this paper, 17 severe typhoons that have affected Hong Kong are simulated using an advanced numerical atmospheric simulation system - Weather Research and Forecasting model (WRF). The simulated surface pressure and wind fields of these typhoons are validated against a wide range of field observations. Then azimuth-dependent models for the radius of maximum winds and the Holland parameter are established statistically at the surface level. It is observed that the shape parameter of the Holland pressure model is smaller at the surface than that at the gradient level. And the Holland wind field model cannot well reproduce the simulated radial wind profiles due to the complexities of nonuniform surface conditions and typhoon dynamics. It is found that the modified Rankine model provides satisfactory estimates of typhoon wind speeds in Hong Kong. Additionally, wind field asymmetries of typhoons approaching Hong Kong are highly correlated with the typhoon track velocity, vertical wind shear and the angle between them. The proposed statistical models and identified characteristics of wind field asymmetries of typhoons will provide useful information for rapidly assessing typhoon wind hazards.</div></div>","PeriodicalId":54752,"journal":{"name":"Journal of Wind Engineering and Industrial Aerodynamics","volume":"254 ","pages":"Article 105934"},"PeriodicalIF":4.2,"publicationDate":"2024-10-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142534109","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-10-22DOI: 10.1016/j.jweia.2024.105927
Jinlin Xia , Gregory A. Kopp , Yaojun Ge
This study delves into the flutter mechanism of a 5,000 m bridge with a wide-slotted deck, finding that the motion is self-sustained and not violently destructive. The system damping ratio is not fixed, and only one stable orbit exists. High-resolution PIV experiments at an experimental wind speed of 10.5 m/s measured the static and dynamic flow fields on the windward and leeward decks. The static results showed leading-edge separation on the windward deck within the reference range, while separation on the leeward deck was difficult to observe. Dynamic testing identified instantaneous vortices around the windward/leeward deck at each phase, with no signs of vortices in the wind speed vectors at all phases after phase-averaging, indicating that the vortex drift hypothesis is not valid. The analysis of the streamline pattern revealed periodic variations in leading-edge separation size and reattachment length on the windward deck during the vibration process, while the leeward deck showed consistently inconspicuous changes. Further examination uncovered a peculiar behavior in the horizontal wind speed profile on the leeward deck during the vibration process, attributed to dynamic changes in the height difference between the windward and leeward decks during flutter. The study suggests that the unusual wind speed profile on the leeward deck is caused by the dynamic changes in height difference between the windward and leeward decks during the flutter process, resulting in additional wind loading. These findings shed light on the complex dynamics of bridge flutter and have implications for the design and maintenance of long-span bridges.
{"title":"Flow field analysis of self-sustained flutter of a wide-slotted bridge deck","authors":"Jinlin Xia , Gregory A. Kopp , Yaojun Ge","doi":"10.1016/j.jweia.2024.105927","DOIUrl":"10.1016/j.jweia.2024.105927","url":null,"abstract":"<div><div>This study delves into the flutter mechanism of a 5,000 m bridge with a wide-slotted deck, finding that the motion is self-sustained and not violently destructive. The system damping ratio is not fixed, and only one stable orbit exists. High-resolution PIV experiments at an experimental wind speed of 10.5 m/s measured the static and dynamic flow fields on the windward and leeward decks. The static results showed leading-edge separation on the windward deck within the reference range, while separation on the leeward deck was difficult to observe. Dynamic testing identified instantaneous vortices around the windward/leeward deck at each phase, with no signs of vortices in the wind speed vectors at all phases after phase-averaging, indicating that the vortex drift hypothesis is not valid. The analysis of the streamline pattern revealed periodic variations in leading-edge separation size and reattachment length on the windward deck during the vibration process, while the leeward deck showed consistently inconspicuous changes. Further examination uncovered a peculiar behavior in the horizontal wind speed profile on the leeward deck during the vibration process, attributed to dynamic changes in the height difference between the windward and leeward decks during flutter. The study suggests that the unusual wind speed profile on the leeward deck is caused by the dynamic changes in height difference between the windward and leeward decks during the flutter process, resulting in additional wind loading. These findings shed light on the complex dynamics of bridge flutter and have implications for the design and maintenance of long-span bridges.</div></div>","PeriodicalId":54752,"journal":{"name":"Journal of Wind Engineering and Industrial Aerodynamics","volume":"254 ","pages":"Article 105927"},"PeriodicalIF":4.2,"publicationDate":"2024-10-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142534120","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-10-19DOI: 10.1016/j.jweia.2024.105921
Deqing Zhu (朱德庆) , Tingguo Chen (陈廷国) , Chengjiao Ren (任珵娇) , Ke Wang (王可)
Porous medium models have long been prevalent numerical computation tools. Although they exhibit swift computational speed, their accuracy in simulating windscreen perforation structures is challenged. This paper introduces the innovative dot-array porous medium (DAPM) model, which accurately portrays the perforation structure and material characteristics of a windscreen by establishing virtual holes on the porous medium. Not only does it simplify modeling by eliminating complex perforation processes, but it also adeptly simulates the flow behavior of the windscreen. The comprehensive comparison between the DAPM model and the physical mesh model, traditional porous medium model, as well as wind tunnel test results, demonstrates that the DAPM model not only possesses rapid computational speed but also delivers outstanding precision in results. In terms of velocity distribution, vortex distribution, and flow intensity in the flow field, the model indicates a high level of accuracy, clearly exceeding that of the porous medium model. Moreover, the DAPM model showcases high versatility and adjustability in practical applications. By adjusting dimension parameters, it demonstrates the capability to precisely simulate any windscreen with holes arranged in a matrix pattern. This research provides an efficient and reliable tool for the numerical simulation of windscreens, with broad application prospects.
{"title":"Dot-array porous medium model for windscreen and its simulation accuracy analysis","authors":"Deqing Zhu (朱德庆) , Tingguo Chen (陈廷国) , Chengjiao Ren (任珵娇) , Ke Wang (王可)","doi":"10.1016/j.jweia.2024.105921","DOIUrl":"10.1016/j.jweia.2024.105921","url":null,"abstract":"<div><div>Porous medium models have long been prevalent numerical computation tools. Although they exhibit swift computational speed, their accuracy in simulating windscreen perforation structures is challenged. This paper introduces the innovative dot-array porous medium (DAPM) model, which accurately portrays the perforation structure and material characteristics of a windscreen by establishing virtual holes on the porous medium. Not only does it simplify modeling by eliminating complex perforation processes, but it also adeptly simulates the flow behavior of the windscreen. The comprehensive comparison between the DAPM model and the physical mesh model, traditional porous medium model, as well as wind tunnel test results, demonstrates that the DAPM model not only possesses rapid computational speed but also delivers outstanding precision in results. In terms of velocity distribution, vortex distribution, and flow intensity in the flow field, the model indicates a high level of accuracy, clearly exceeding that of the porous medium model. Moreover, the DAPM model showcases high versatility and adjustability in practical applications. By adjusting dimension parameters, it demonstrates the capability to precisely simulate any windscreen with holes arranged in a matrix pattern. This research provides an efficient and reliable tool for the numerical simulation of windscreens, with broad application prospects.</div></div>","PeriodicalId":54752,"journal":{"name":"Journal of Wind Engineering and Industrial Aerodynamics","volume":"254 ","pages":"Article 105921"},"PeriodicalIF":4.2,"publicationDate":"2024-10-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142534119","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-10-19DOI: 10.1016/j.jweia.2024.105928
Yunqiang Wu , Yue Wu , Ying Sun , Xiaoying Sun
The cable support photovoltaic module system has obvious characteristics of wind-induced vibration. In order to study the wind-induced vibration response characteristics and mechanism of the double-cable support photovoltaic module systems, and further discuss the stiffness control criterion. The wind-induced vibration response of a new type of cable-truss support photovoltaic module system with a span of 35m is studied through the aeroelastic wind tunnel test. Firstly, the scaled aeroelastic test model was established to meet the aeroelastic test requirements. Then, the effects of wind direction, PV module inclination angle, and stability cable initial prestress on the wind-induced vibration response characteristics under uniform flow and turbulent field are studied. Finally, the wind-induced vibration response mechanism and stiffness control criterion are discussed. The results show that the increase of inclination angle will lead to a decrease in critical wind speed, the 0° wind direction is the most unfavorable, and the increase of initial prestress can increase the critical wind speed but is inefficient. The critical wind speed under the turbulent flow field is about 30% higher than that of the uniform flow field. The instability vibration is the result of multi-mode coupled vibration of vertical bending and torsion. It is suggested that the stiffness control criterion is more appropriate as 1/100. The research results are of great significance for the design and application of the cable support photovoltaic module system.
{"title":"Wind-induced response and control criterion of the double-layer cable support photovoltaic module system","authors":"Yunqiang Wu , Yue Wu , Ying Sun , Xiaoying Sun","doi":"10.1016/j.jweia.2024.105928","DOIUrl":"10.1016/j.jweia.2024.105928","url":null,"abstract":"<div><div>The cable support photovoltaic module system has obvious characteristics of wind-induced vibration. In order to study the wind-induced vibration response characteristics and mechanism of the double-cable support photovoltaic module systems, and further discuss the stiffness control criterion. The wind-induced vibration response of a new type of cable-truss support photovoltaic module system with a span of 35m is studied through the aeroelastic wind tunnel test. Firstly, the scaled aeroelastic test model was established to meet the aeroelastic test requirements. Then, the effects of wind direction, PV module inclination angle, and stability cable initial prestress on the wind-induced vibration response characteristics under uniform flow and turbulent field are studied. Finally, the wind-induced vibration response mechanism and stiffness control criterion are discussed. The results show that the increase of inclination angle will lead to a decrease in critical wind speed, the 0° wind direction is the most unfavorable, and the increase of initial prestress can increase the critical wind speed but is inefficient. The critical wind speed under the turbulent flow field is about 30% higher than that of the uniform flow field. The instability vibration is the result of multi-mode coupled vibration of vertical bending and torsion. It is suggested that the stiffness control criterion is more appropriate as 1/100. The research results are of great significance for the design and application of the cable support photovoltaic module system.</div></div>","PeriodicalId":54752,"journal":{"name":"Journal of Wind Engineering and Industrial Aerodynamics","volume":"254 ","pages":"Article 105928"},"PeriodicalIF":4.2,"publicationDate":"2024-10-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142534107","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
扫码关注我们
求助内容：
应助结果提醒方式：
京公网安备 11010802042870号