DEM-LBM simulation of multidimensional fractionation by size and density through deterministic lateral displacement at various Reynolds numbers

Simulative Investigation of Different DLD Microsystem Designs with Increased Reynolds Numbers Using a Two-Way Coupled IBM-CFD/6-DOF Approach

“…Cyclic boundary conditions were not chosen for the lateral boundaries, since they induced an artificial anisotropy in the velocity field. This means that the velocity averaged over the simulation field in the case of lateral cyclic boundary conditions has a nonzero lateral component, as already observed by [38,39], which affects the periodicity of the system [30]. In contrast, when choosing wall boundary conditions in the lateral direction, a pressure gradient normal to the flow was observed, highlighting that cyclic boundary conditions in this direction are unsuitable.…”

“…Various numerical methods have been used so far to characterize the flow and particle behavior in DLD microsystems. A distinction can be made between calculations of the steady-state flow field [14,[17][18][19][20][21] and simulations that include particle dynamics [8,15,[22][23][24][25][26][27][28][29][30][31][32][33][34]. The calculation of the velocity field only allows for an estimation of the behavior of particles in the flow and the d c , but the interactions between particles and the fluid are neglected.…”

“…The calculation of the velocity field only allows for an estimation of the behavior of particles in the flow and the d c , but the interactions between particles and the fluid are neglected. The fluid-structure interactions are either calculated in direct numerical simulations (DNS) [25][26][27][28][29]32] or the fluid and solid phases are calculated in separate processes, and both methods are coupled iteratively; for example, the lattice Boltzmann method (LBM) coupled with the discrete element method (LBM-DEM) [30] or coupled with the finite element method (FEM) [31]. The fluid-structure simulations were either simplified into two dimensions [8,15,[22][23][24]28,32,34,35] or calculated in a more complex three-dimensional way [25][26][27][29][30][31].…”

“…The fluid-structure interactions are either calculated in direct numerical simulations (DNS) [25][26][27][28][29]32] or the fluid and solid phases are calculated in separate processes, and both methods are coupled iteratively; for example, the lattice Boltzmann method (LBM) coupled with the discrete element method (LBM-DEM) [30] or coupled with the finite element method (FEM) [31]. The fluid-structure simulations were either simplified into two dimensions [8,15,[22][23][24]28,32,34,35] or calculated in a more complex three-dimensional way [25][26][27][29][30][31]. In addition, the calculations differ in whether only the forces (and moments) that the fluid exerts on the particles are calculated (one-way coupling) [11,23] or whether particle feedback to the fluid takes place (two-way coupling) [22,24,[26][27][28]36].…”

“…The use of two-dimensional coupled simulations saves computational costs, but it ignores the fact that particles in fluids move in a threedimensional mode and that deviations are to be expected in the forces on the particles [37]. Some works also consider particle rotation in their calculations, allowing for rotationinduced lift forces [25,26,28,30,33]. Only few works dissolve or model short-range repulsive viscous (lubrication) forces [9,29,32,33] In this work, a model was developed to represent particle transport within a DLD microsystem.…”