Comparison of sharp and smoothed interface methods for simulation of particulate flows II: Inertial and added mass effects

Abstract

This paper studies the robustness of the Smoothed Profile Method (SPM) in fluid-solid interaction problems where inertia and added mass effects are significant. The performance of SPM is compared with that of a Sharp Interface Method (SIM), which is constructed with second-order discretization schemes. The applicability of SPM is extended to the moderate Reynolds numbers regime where the boundary layer and wake dynamics are likely to be influenced by the thickness of the solid-fluid interface. It is shown that SPM is able to correctly predict the drag and surface vorticity forRe<O(104). In comparison with SIM, SPM is more robust on coarse grids for Re<O(104); however, SPM needs fine grids to produce accurate results when Re∼O(104). SPM and SIM are also applied to fluid structure interaction (FSI) problems using an implicit fluid-solid strong coupling framework. This allows computations of FSI problems with moderate inertia and low particle to fluid density ratios (high added mass effects). The effect of the smoothed interface on accuracy and robustness is assessed for such FSI problems. Results indicate that SPM is more robust than SIM when the density of the particle is comparable to the fluid, i.e. for high added mass effects.