A resolved CFDEM method for the interaction between the fluid and the discontinuous solids with large movement

Abstract

Summary A novel resolved combination of the computational fluid dynamics and the discrete element method (CFDEM) is proposed for the simulation of the strong coupling between the fluid and the discontinuous solids with large movement. The fluid flow governed by the full Navier‐Stokes equations is simulated using fixed grids based on the Eulerian framework, whereas the motion of the discontinuous solids is modeled by the discrete element method using the Lagrangian description. The key challenge, namely, the representation of the moving interfaces between the fluid and the solids in different frameworks, is handled by the immersed boundary method. Meanwhile, the governing equations of the coupled system are solved by the partitioned method in an iterative way to achieve a strong coupling effect. The breakthrough of the proposed resolved CFDEM method lies in the calculation of the fluid flow in fixed grids with high resolution, along with an accurate simulation of the interaction between the fluid and the discontinuous solids with arbitrary shapes and large movement. The reliability and the accuracy of the new method are validated by calculating several well‐known benchmark examples. Good agreements are achieved between the present and the known results.