Effect of pantograph bionic deflectors on aerodynamic performance of high-speed under crosswind
The side force and the rolling moment will increase significantly under crosswind,and the aerodynamic performance of high-speed trains will change significantly.The possibility of train derailment and overturning will increase greatly,which will have a serious impact on the safety of train operations.As a core component of high-speed trains,pantographs are seriously affected by crosswinds.Based on the biological pattern of Coleoptera,the geometric shape of the pantograph bionic elytra(i.e.,deflector)was constructed in an eight-car group mode.Therefore,four calculation cases were obtained,i.e.,the original model(model Ⅰ),only pantograph Ⅰ with a deflector(model Ⅱ),only pantograph Ⅱ with a deflector(model Ⅲ),and both pantograph Ⅰ and Ⅱ with deflectors(model Ⅳ).Based on the three-dimensional steady SST k-ω two-equation turbulence model,the aerodynamic performance of the high-speed train and the pantograph area under crosswind in different schemes was discussed.The results are drawn as follows.The air flows over the pantograph area in a smoother way with less blockage effect as compared to the base case without deflectors,resulting in an increase in the airflow velocity at the top of the downstream train body and the pantograph Ⅱ(rising pantograph)area,and the flow field structure of the leeward side of the train changes.Compared with the original model(model Ⅰ),the deflector models(models Ⅱ,Ⅲ and Ⅳ)contribute to the reduction of side force and the rolling moment.The side force of model Ⅱ and model Ⅲ are reduced by 9.65%and 4.18%respectively,and the rolling moment is reduced by 11.47%and 4.37%respectively.The effect of model Ⅳ,in which both pantograph Ⅰ and pantograph Ⅱ are wrapped,is the most significant,and the side force and rolling moment of the whole car of the 8-car formation are reduced by 11%and 4.37%respectively.The side force and rolling moment of the 8-vehicle group are reduced by 11.39 and 16.81%respectively.The research results can provide a reference for the optimal design of the pantograph area for new-generation high-speed trains under crosswind.
high-speed pantographbionic deflectorcrosswind adaptationvelocity distribution
万方数据
维普
