Traditional track dynamic geometric state(TDGS)simulation incurs substantial computational burdens,posing challenges for developing reliability assessment approach that accounts for TDGS.To overcome these,firstly,a si...Traditional track dynamic geometric state(TDGS)simulation incurs substantial computational burdens,posing challenges for developing reliability assessment approach that accounts for TDGS.To overcome these,firstly,a simulation-based TDGS model is established,and a surrogate-based model,grid search algorithm-particle swarm optimization-genetic algorithm-multi-output least squares support vector regression,is established.Among them,hyperparameter optimization algorithm’s effectiveness is confirmed through test functions.Subsequently,an adaptive surrogate-based probability density evolution method(PDEM)considering random track geometry irregularity(TGI)is developed.Finally,taking curved train-steel spring floating slab track-U beam as case study,the surrogate-based model trained on simulation datasets not only shows accuracy in both time and frequency domains,but also surpasses existing models.Additionally,the adaptive surrogate-based PDEM shows high accuracy and efficiency,outperforming Monte Carlo simulation and simulation-based PDEM.The reliability assessment shows that the TDGS part peak management indexes,left/right vertical dynamic irregularity,right alignment dynamic irregularity,and track twist,have reliability values of 0.9648,0.9918,0.9978,and 0.9901,respectively.The TDGS mean management index,i.e.,track quality index,has reliability value of 0.9950.These findings show that the proposed framework can accurately and efficiently assess the reliability of curved low-stiffness track-viaducts,providing a theoretical basis for the TGI maintenance.展开更多
This work deals with a description of a parametric tool for elastic analysis of wind turbine tower, incorporating all analysis steps （preprocessing, processing and post-processing）. The tower geometry is approximate...This work deals with a description of a parametric tool for elastic analysis of wind turbine tower, incorporating all analysis steps （preprocessing, processing and post-processing）. The tower geometry is approximated by fiat elements in which the membrane effects are evaluated using the FF （free formulation） finite element and the flexure effects are calculated using DKT （discrete shear triangle） finite element. The user-friendly system is implemented using OpenGL library to provide the graphical construction for geometry, mesh orientation, and other requirements of the finite element model. For the processing stage is built a specific dll library implemented in C＋＋ language for the analysis using the FF and DKT finite elements. The post-processing stage is build using specific dialogs box to present all results. The displacement results are visualized in the graphic interface to show the static and dynamic deformations of the tower. Some examples are presented to show all the tasks of the parametric tool.展开更多
基金Project(52072412)supported by the National Natural Science Foundation of China。
文摘Traditional track dynamic geometric state(TDGS)simulation incurs substantial computational burdens,posing challenges for developing reliability assessment approach that accounts for TDGS.To overcome these,firstly,a simulation-based TDGS model is established,and a surrogate-based model,grid search algorithm-particle swarm optimization-genetic algorithm-multi-output least squares support vector regression,is established.Among them,hyperparameter optimization algorithm’s effectiveness is confirmed through test functions.Subsequently,an adaptive surrogate-based probability density evolution method(PDEM)considering random track geometry irregularity(TGI)is developed.Finally,taking curved train-steel spring floating slab track-U beam as case study,the surrogate-based model trained on simulation datasets not only shows accuracy in both time and frequency domains,but also surpasses existing models.Additionally,the adaptive surrogate-based PDEM shows high accuracy and efficiency,outperforming Monte Carlo simulation and simulation-based PDEM.The reliability assessment shows that the TDGS part peak management indexes,left/right vertical dynamic irregularity,right alignment dynamic irregularity,and track twist,have reliability values of 0.9648,0.9918,0.9978,and 0.9901,respectively.The TDGS mean management index,i.e.,track quality index,has reliability value of 0.9950.These findings show that the proposed framework can accurately and efficiently assess the reliability of curved low-stiffness track-viaducts,providing a theoretical basis for the TGI maintenance.
文摘This work deals with a description of a parametric tool for elastic analysis of wind turbine tower, incorporating all analysis steps （preprocessing, processing and post-processing）. The tower geometry is approximated by fiat elements in which the membrane effects are evaluated using the FF （free formulation） finite element and the flexure effects are calculated using DKT （discrete shear triangle） finite element. The user-friendly system is implemented using OpenGL library to provide the graphical construction for geometry, mesh orientation, and other requirements of the finite element model. For the processing stage is built a specific dll library implemented in C＋＋ language for the analysis using the FF and DKT finite elements. The post-processing stage is build using specific dialogs box to present all results. The displacement results are visualized in the graphic interface to show the static and dynamic deformations of the tower. Some examples are presented to show all the tasks of the parametric tool.
