真空管道超级列车激波簇结构研究

Research on Shock Wave Trains Generated by the Hyper Train in the Evacuated Tube

真空管道列车高速飞行时产生的激波簇对于车辆结构气动外形设计具有重要的指导作用。鉴于真空管道超级列车现有试验设备及方法的局限性,根据可压缩N-S方程和SST k-w湍流模型,基于计算流体动力学(Computational fluid dynamics,CFD)流体分析软件,结合动网格和动态自适应网格两种方法,对超级列车在高真空度管道中高速运动时产生的流场结构进行数值仿真,主要研究列车以1 250 km/h的速度在阻塞比为0.2、环境压力为10.132 5 Pa(0.000 1 atm)的管道中飞行时所产生的一系列激波簇结构及管内流场变化规律。研究结果表明,管内列车在管内飞行时产生弓形激波、正激波、反射激波、Lamda激波、菱形激波等激波簇结构;头车附近区域会出现弓形激波、反射激波向正激波转化的过程,中间车附近区域会出现反射激波、菱形激波产生、发展与消失的过程,尾车附近区域会出现Lamda激波、反射激波、菱形激波、正激波的发展过程。

Shock wave trains generated by the high-speed flight train in the evacuated tube play an important role in aerodynamic shape design of the vehicle. In view of the constraints of existing equipment and experiment method, the flow field structure generated around the hyper train in the high vacuum tube is numerically simulated by computational fluid dynamics software. Based on the compressible N-S equation, shear stress transport k-w turbulence model and combination method of the dynamic mesh with adaptive mesh. In the simulation, shock wave trains’ structure and change law of the flow field inner the tube are studied when the train operates at the speed of 1 250 km/h in the tube with blockage ratio of 0.2 and environment pressure of 10.132 5 Pa(0.000 1 atm). The results show that bow shock wave, normal shock wave, reflected shock wave, lamda shock wave and diamond shape shock wave are produced as the train is flying in the tube. The process that bow shock wave and reflected shock wave are transformed into the normal shock wave in the vicinity of the head car has appeared. The process that reflection shock wave and diamond shape shock wave are produced, developed and disappeared in the vicinity of the mid car has appeared. The development process of the lamda shock wave, reflected shock wave, diamond shape shock wave and normal shock wave appear in the vicinity of the tail car.