| With the increasing of the train speed,the effect of aerodynamic force on the pantograph of high-speed train becomes more significant with the increase of the train speed,thus affecting the safety performance of the train operation.Therefore,considering the influence of aerodynamics on pantograph and optimizing the pantograph structure aerodynamics are of great significance to the safe operation and development of high-speed trains.This paper takes the high speed pantograph aerodynamics as the research object to optimize the pantograph section shape.Based on the aerodynamics theory,the fluid mechanics analysis software Fluent was used to compare and study the flow field and mechanical characteristics around the pantograph before and after optimization.First of all,this paper discusses the basic theoretical knowledge of aerodynamics,which provides a theoretical basis for the establishment of the pantograph head aerodynamics model and the further analysis of the pantograph air pressure field,velocity field and mechanical characteristics.Secondly,according to the principle of penguin swimming bionics,five different bionic pantograph 2-D cross-section models were constructed,which were rectangular pantograph,long curved pantograph,short semicircular pantograph,short triangular pantograph,and long triangular pantograph.The aerodynamic characteristics of pantograph with different cross sections were analyzed under different operating speeds,and the velocity and pressure distribution of the flow field around the pantograph with different cross sections,as well as the resistance and lift characteristics of the pantograph were compared and studied.The results show that the aerodynamic performance of the long curved section is the best,and the aerodynamic resistance of the linear section is obviously less than that of the angular section.Finally,the three-dimensional model structures of long curve pantograph head and rectangular pantograph head are established,and the aerodynamic characteristics and aerodynamic noise characteristics of long curve pantograph and rectangular pantograph are numerically simulated,and the dynamic characteristics and aerodynamic noise characteristics of them are compared.The results show that the long curved pantograph can reduce drag and noise to a certain extent,because the fluid flowing through the curved surface can effectively reduce the loss of trailing vortexes,and the aerodynamic resistance is greatly reduced.At 350km/h,the maximum broadband noise of the pantograph is reduced by 9 d B,indicating that the long curved bow has better aerodynamic characteristics.Noise reduction effect is obvious. |
