A DSMC implement method of a hybrid grid of molecular motion and collision
Based on the strategy of combining unstructured grid with Cartesian grid,a double grid DSMC method for molecular motion and collision is proposed.Through the position information of molecules,the contact between the moving grid and the collision grid is established,which combines the body-fitting of an unstructured grid and the advantage of being easy to control the number of subgrids of a Cartesian grid.At the same time,a technique of dynamic self-adaptation subgrids based on MCS is proposed and implemented to improve the applicability and computational accuracy of the DSMC method,which effectively limits the mean collision separation of molecules.The effectiveness and high precision of the DSMC method are verified by numerical simulation of the flow around a supersonic cylinder and an expanding pipeline.Numerical results show that the resolution of the flow field around the supersonic cylinder can be enhanced through the DSMC method based on molecular motion and collision double grids,and the mean collision separation through the self-adaptive dynamic subgrids technique can be effectively reduced,the collision quality and the calculation accuracy can be improved.
double gridDSMCmean collision separationstatic technology of subgridsself-adaptive dynamic technology of subgrids