高速列车不同头部形状的气动性能研究

Study on the performances of aerodynamics of highspeed train with different nose shapes

就几种典型形状列车车头,在简化列车外形的情况下,针对高速列车不同运行速度下的气动阻力和升力进行计算.为计算阻力和升力系数,将三维雷诺平均化N-S方程(RANS)结合k-ε湍流模型,用有限体积法(FVM)将控制方程离散求解.用SIMPLE法耦合压力-速度场,通过解类Poisson方程,对压力迭代地修正.模拟计算结果显示采用向首部有收缩的头部形状可获得较好的空气动力学性能;综合考虑与权衡稳定性与机动性,在更高速情况下运行的列车宜优先采用向首部有收缩的头部形状.图7,参12.

For serveral typical nose shapes of highspeed train, results of numerical investigations of aerodynamic drag and lift coefficents of flows past a simplified train geometry under different train speed are summarised. To compute numerically the different coefficents, the three-dimensional Reynolds-averaged Navier-Stokes equations（RANS）, combined with the k-e turbulence model, were solved using finite volume technique. The pressure-velocity fields were coupled using the SIMPLE algorithm. At each iteration the pressure correction was obtained by solving avelocity divergence-derived Poisson-like equation. Results of numerical investigations show the nose shape which shrinks noseward should be adopted to obtain good performances of aerodynamics. Manoeuvre stability and flexibility should be considered and weighed synthetically.