An improved penalty immersed boundary method for multiphase flow simulation

作者：Huang, Wei-Xi^*; Guo, Wei

来源：International Journal for Numerical Methods in Fluids, 2018, 88(9): 447-462.

DOI：10.1002/fld.4674

• multiphase flow
• nonuniform density
• penalty immersed boundary method
• reinitialization
• surface tension

An improved version of the penalty immersed boundary method is proposed for simulating multiphase flows with nonuniform density and moving interface. The background fluid with a uniform density is solved on the fixed Eulerian grid, while the excessive mass is modelled by the Lagrangian points. Both the positive and negative density differences are taken into account, and the surface tension is included in the formulation. For validation of the present method, the Rayleigh-Taylor instability problem and deformation of a droplet in a simple shear flow are computed. The numerical results are compared with the previous studies and the spatial accuracy is between the first and second order. Convergence of the computational results as the penalty coefficient increases is obtained. Furthermore, interaction of the fluid-fluid interface with the rigid surface is also considered. To improve the numerical stability, the reinitialization operation is introduced to guarantee the quality of the Lagrangian mesh. As a demonstrating example, a droplet bypassing an obstacle in a channel flow is tested.

• 出版日期2018-11-30
• 单位清华大学