Numerical Simulation Of Flow Around. Outside The Three-dimensional Car

For the cars at high speeds, the air drag occupies most of the total running resistance and the lifting force along with the side force has great influence on the driving stability, the running safty and so on, so the study about the external flow field around the car surface is of great importance. The numerical simulation of the external flow will be done in this thesis. The main parts are as the following:1 The physical and mathematical models for the external flow field around the car surface are set up in three dimensions.2 The hybrid meshes for the seperated zones of the external flow field are generated using the structured, unstructured and the semi-structured grids.3 The RANS Equations are discretized with the FVM method and the equations of the pressure and velocity are solved with the SIMPLE algorithm in a coupling method.4 The optimal turbulence model and the wall function are selected by the numerical validation.5 The simulation on the external flow field around the car surface is well finished. The flow characteristics are carefully analyzed. The effect of the moving ground and the accuracy of the meshes are also discussed. The numerical results are in good agreement with those from experiment.