基于压力分布的高速列车气动力计算方法

基于径向基函数的气动压力插值方法和摩擦力计算模型,提出了一种可用于高速列车线路试验的气动力快速计算方法。该方法只需测得车体表面若干测点的压力,然后基于这些测点的压力值,使用径向基函数插值方法得到车体表面压力分布;并采用数值积分方法与平板边界层摩擦力计算模型能够快速得到气动压差力和气动摩擦力。列车附属部件几何外形复杂,难以通过插值方法获取表面压力分布;为此,基于八辆编组真实外形,给出了各附属部件对列车气动力贡献度,从而使本文提出的方法能够应用于线路试验和动模型试验。为验证计算方法的有效性,针对高速列车三辆编组简化外形头尾车流线型部分,采用数值计算方法对比分析了气动阻力和气动升力计算结果与计算结果;针对三辆编组风洞试验外形分析了气动阻力试验值和计算值。结果表明:提出的计算方法能够满足工程精度要求。

An Aerodynamic Force Computation Method of High Speed Trains Based on Pressure Distribution

Based on the radial basis function (RBF) method and the friction computation model, a method to calculate the aerodynamic force of the high-speed train when it is running on the railway is proposed. The pressure of many points on the carriage body should be measured to fit the pressure distribution of the carriage surface with the RBF, and then the pressure force and shear force can be obtained with the numerical integral method and the flat plate boundary layer friction computation model. The geometry of affiliated parts is so complex that the surface pressure distribution cannot be calculated by RBF. Therefore, the contribution of affiliated parts is given based on the eight car real shape so that the proposed method can be used to the railway test and moving model test. To validate effectiveness of the method, the CFD results and the calculation results of the aerodynamic drag force and lift force of the streamline parts of simplified high speed train with a leading car, a middle car and a trailing car are discussed. Besides, the wind tunnel test results and the calculation results of the real shape with a leading car, a middle car and a trailing car are compared. The results show that the computation method proposed in this paper can meet the engineering accuracy.