Direct imposition of the wall boundary condition in smoothed particle hydrodynamics

Abstract

In this study, a new method for treating the wall boundary in smoothed particle hydrodynamics (SPH) is proposed to simulate fluid flows effectively. Unlike conventional methods of wall boundary treatment through boundary particles, in the proposed method, the wall boundary condition is directly imposed by adding boundary truncation terms to the mass and momentum conservation equations. Thus, boundary particles are not used in boundary modeling. Doing so, the wall boundary condition is accurately imposed, boundary modeling is simplified, and computation is made efficient without losing stability in SPH. In addition, we propose a analysis strategy for fluid–structure interaction through coupling with the finite element method (FEM) based on the feature of the proposed method that the boundary is modeled in the mesh shape. Performance of the proposed method is demonstrated through several numerical examples: dam break, dam break with a wedge, sloshing, inclined bed, cross-lever rotation, pulsating tank, Poiseuille flow, Couette flow, and heat convection in square cavity in 2D, Poiseuille flow, dam break, and sloshing in 3D. These results are compared with available experimental results, analytical solutions, and results obtained using the boundary particle method.