关键词: 辐射流体力学, 抛物型方程, 九点差分格式, 扭曲网格

Abstract: Construction of difference schemes for parabolic equations on distorted meshes with large aspect ratio is discussed.The limitation of 9-point scheme is provided.An assistant mesh difference method is proposed for distorted meshes with large aspect ratio to improve precision and efficiency.Based on the conservation law,applying appropriate rezone methods for meshes we modify the 9-point method to reduce computation error due to poor regularity of the meshes and low precision due to the approximation to vertices values by an average of neighboring cell values.The nonlinear system obtained is a different system from the 9-point scheme.Its solution approximates to the solution with the original meshes.The designed scheme is implemented easily and adapts well to distorted meshes.Numerical experiments show good precision and stability.

Key words: radiation hydrodynamics, parabolic equation, 9-point difference scheme, distorted mesh