Direct Numerical Simulation Study of Hydrodynamic Interactions between Immersed Solids and Wall During Flow

Chaotic orbits of tumbling ellipsoids

“…In our simulations, we have chosen D p as the longest axis a of the ellipsoid. We have developed an in-house solver, termed the Gerris immersed solid solver (GISS) (Shui et al 2015) for our DNS. For solids immersed in inviscid fluids we cross-validate our DNS results against theoretical solutions of the Kirchhoff equations for inviscid fluids.…”

“…The experiments were simulated using a sufficiently spacious domain, to eliminate the effect of the side boundaries (L/D p = 32). Our previous rigorous studies (Shui et al 2015) suggested that a sixteenfold mesh refinement, defined as R m = 1/16, was dense enough around the body to accurately simulate settling.…”

“…In figure 5 the Reynolds number based on the body's longest axis is 0.1, and we have checked, using the theory of Einarsson et al (2015), that the finite Reynolds number corrections to Jeffery orbits for our biggest aspect ratio are three orders of magnitude smaller than the effects we retain. Note that only a sample from an exhaustive validation study available in Shui et al (2015) has been presented here.…”

Simulation and optimization of a lamella settler for cattle feedlot wastewater treatment and nutrients recovery. Experimental validation in the field

“…Simulations were performed using the Gerris Flow Solver CFD open-source software ( Popinet, 2003 ) in a 2D arrangement. Gerris has been applied to interpret the underlying dynamics of multiphase flows and phases interactions in several systems ( Keen et al., 2013 ; Salvador et al., 2016 ; Shui et al., 2015 ). In this study, the simulation of the liquid and flocs motion in the lamellar settler was carried out using the incompressible fluid Navier-Stokes DNS solver with an octree data structure for mashing ( Lagrée et al., 2011 ; Popinet, 2003 ), in a two-dimensional arrangement (U z = 0).…”