高速动车组转向架积雪特性数值仿真及优化设计

Numerical Simulation on Snowpack Characteristics of High-speed EMU Bogie and Optimization Design

基于三维不可压缩Navier-Stokes方程和RNG k-ε双方程湍流模型,对350 km/h高速动车组明线运行转向架周围空气流场进行数值分析,采用离散相模型对路面积雪引起的转向架风雪两相流流场进行数值研究。结果表明,转向架周围流场存在的大量空气涡流,影响了转向架周围的空气压力分布。转向架表面的雪花颗粒黏附堆积情况与转向架的安装位置及其周围的空气流场压差有关。中间车第一个转向架颗粒黏附数量最多,尾车第二个转向架黏附数量最少。通过优化转向架周围的裙板结构,转向架周围的空气压力有明显变化,转向架周围垂向方向空气压力差有减小趋势,转向架表面及前后导流板雪花颗粒黏附堆积数目比原方案降低了51.03%。

Based on three-dimensional incompressible Navier-Stokes equations and the RNG k-ε turbulence model, the air flow field surrounding the bogies was analyzed when high-speed EMU ran in open air at 350 km/h, and then the flow field of the bogie’s wind-snow two phase flow caused by the snow on the roadbed was simulated through discrete phase model. The results show that a large amount of air vortex exists in the bogie flow field, which affects the air pressure distribution around the bogies. The adhesion and accumulation of snow particles on the surface of the bogie are related to the installation position of the bogie and the air flow field differential pressure around the bogie. The number of particles adhering to the first bogie of the intermediate car is the largest, while the number of particles adhering to the second bogie of the tail car is the least. By optimizing the apron structure around the bogie, the air pressure is changed obviously around the bogie, and the air pressure differential along the bogie vertical direction decreases. Compared to the original plan, the number of adhesion and accumulation of snow particles is reduced by 51.03% on the bogie surface and front and back guide plates.