大风下高速列车单车出隧道空气动力效应数值模拟初探

发布时间：2018-05-05 23:58

本文选题：高速列车 + 大风　；参考：《兰州交通大学》2014年硕士论文

【摘要】：车辆驶出隧道过程中受到很强的列车风作用，气动力非常复杂。而如果列车在驶出隧道的过程中，同时遭遇到外界大风的话，所受到的风载荷将更加复杂，在此作用下，车辆的动力学恶化，车辆的运行安全性将受到严重的影响。我国地貌广阔，风力资源十分丰富。西北地区常年大风，兰新线既有线上常因大风导致列车晚点，严重时，导致列车翻车。即将投入运营的兰新第二双线要途径甘肃、青海和新疆三省，穿越五大风区，全线长1776km，其中有579.599位于大风区，占全线长的32.8%。新疆境内通过大风区线路长度为462.409，占新疆境内线路总长的64.8%。此外，兰新第二双线有11座隧道位于四大风区。可见研究列车在大风下驶出隧道的过程是很有必要的。本文模拟中，列车模型选用带转向架、受电弓导流罩及风挡的较真实的CRH2型列车模型，隧道洞门选用帽檐切削式洞门。由于选用的列车模型和隧道模型几何形状比较复杂，因此利用ICEM-CFD软件在列车周围和计算区域生成非结构化的Tetra网格。另外本文采用滑移网格技术模拟列车驶出隧道的过程，滑移网格技术对滑移面两侧的网格要求较高，因此利用ICEM-CFD软件在滑移面两侧生成结构化的Hexa网格，再与Tetra网格融合。本文模拟中选用STAR-CD软件进行模拟计算，模拟中，为了避免直接启动引起的非物理现象，采用光滑启动技术。湍流模型选用高雷诺数SST模型，在合理的边界条件和初始条件的基础上，采用PISO算法求解雷诺时均方程，用中心差分法离散扩散项，用MARS差分格式离散对流项，用CG方法求解离散后的代数方程组。在此基础上模拟了列车驶出隧道的全过程。本文研究了列车以200km h的速度在30m s的风速下驶出隧道过程中车体表面压力及所受到的侧向力、升力和倾覆力矩的变化过程，并研究了这一工况下隧道外流场的变化。进而对比了30和60两种风速下，列车以200、220、250的速度驶出隧道，侧向力、升力和倾覆力矩的不同，得出了列车速度对流场的影响和风速对流场的影响。本文所采用的网格融合技术可望为后续对较真实列车模型的研究提供有益的帮助，，本文模拟中所得到的结论可望为后续的研究提供有益的参考。
[Abstract]:The aerodynamic force is very complicated because of the strong train wind in the course of the vehicle exiting the tunnel. If the train encounters a strong wind in the process of exiting the tunnel, the wind load will be more complicated. Under the action, the vehicle dynamics will deteriorate and the safety of the vehicle will be seriously affected. Our country geomorphology is broad, wind energy resource is very rich. In Northwest China, the train is delayed because of the strong wind, and when it is serious, the train overturns. The second double line of Lanxin, which will be put into operation, will pass through Gansu, Qinghai and Xinjiang provinces, passing through the five gale areas. The whole line is 1776km long, of which 579.599 are located in the gale area, accounting for 32.8km of the total length of the line. The length of transmission line in Xinjiang is 462.409, which accounts for 64.8% of the total length of line in Xinjiang. In addition, the second double-lane Lanxin 11 tunnels located in the four-strong area. Therefore, it is necessary to study the process of the train going out of the tunnel under the strong wind. In the simulation of this paper, the actual CRH2 train model with bogie, pantograph guide cover and windshield is used in the train model, and the Hatter cutting door is used in the tunnel portal. Due to the complex geometry of the train model and tunnel model, the ICEM-CFD software is used to generate unstructured Tetra mesh around the train and the computing area. In addition, the sliding grid technology is used to simulate the process of train exit from the tunnel. The sliding grid technology requires higher grid on both sides of the slip plane, so the ICEM-CFD software is used to generate structured Hexa mesh on both sides of the slip surface and then merge with the Tetra grid. In order to avoid the non-physical phenomenon caused by direct startup, the smooth startup technique is adopted in this paper. In order to avoid the non-physical phenomena caused by direct startup, the STAR-CD software is used to simulate and calculate. The high Reynolds number SST model is used in the turbulent model. On the basis of reasonable boundary conditions and initial conditions, the PISO algorithm is used to solve the Reynolds time-averaged equation, the central difference method is used to discretize the diffusion term, and the MARS difference scheme is used to discretize the convection term. The CG method is used to solve the discrete algebraic equations. On this basis, the whole process of train exiting the tunnel is simulated. In this paper, the variation process of the surface pressure, lateral force, lift force and overturning moment of the train in the course of moving out of the tunnel at the speed of 200km h at the wind speed of 30 Ms is studied, and the variation of the tunnel flow field under this condition is also studied. Furthermore, the difference of lateral force, lift and overturning moment between 30 and 60 kinds of wind speed is compared, and the influence of train velocity field and wind velocity flow field is obtained. The mesh fusion technique used in this paper is expected to provide useful help for the further study of the real train model, and the conclusions obtained in the simulation in this paper are expected to provide a useful reference for further research.
【学位授予单位】：兰州交通大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：U270.11;U451.3

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