不可压粘性流体浸入边界直接力法及软件实现

浸入边界法通过在N-S方程中施加体积力模拟不可滑移固壁边界及动边界，避免生成复杂贴体网格及动网格，极大地节省了网格建模时间及动网格计算消耗。本文提出一种新型附加体积力简化计算方法，将简化附加体积力以源项形式嵌入动量方程迭代中，通过用户自定义函数对CFD软件FLUENT二次开发，实现了浸入边界法和通用流体力学求解器的耦合计算。通过静止圆柱和动圆柱绕流数值模拟进行了验证，并探讨了插值函数对计算精度的影响。研究表明，通过引入浸入边界模型，能够提高计算效率，并实现结构网格背景下复杂边界和动边界的高效建模。

Direct-forcing immersed boundary method for incompressible viscous flowand its software implementation

Immersed boundary method can simulate non-slip solid wall boundary and moving boundary by adding body force in N-S equation,avoiding generating complicated body-fitting grid and moving grid,which saves meshing time and computing cost.A new simplified calculation method for body force is presented.By user-level development of CFD software FLUENT through user-defined function,the simplified body force is embedded into the iteration of momentum equation in the form of the source term,realizing the coupling calculation between immersed boundary method and general fluid mechanics solver.The model for non-slip solid wall boundary and moving boundary is verified by the numerical results of flow past a two-dimensional stationary and moving circular cylinder,and the effects of different interpolation functions for the immersed boundary method are discussed.The research shows that by introducing IBM model into FLUENT,the efficient modeling of complex boundary and moving boundary can be realized on the premise of significantly improving computational efficiency.