A comparative study of fluid-particle coupling methods for fully resolved lattice Boltzmann simulations

Abstract

The direct numerical simulation of particulate systems offers a unique approach to study the dynamics of fluid-solid suspensions by fully resolving the submerged particles and without introducing empirical models. For the lattice Boltzmann method, different variants exist to incorporate the fluid-particle interaction into the simulation. This paper provides a detailed and systematic comparison of two different methods, namely the momentum exchange method and the partially saturated cells method by Noble and Torczynski. Three subvariants of each method are used in the benchmark scenario of a single heavy sphere settling in ambient fluid to study their characteristics and accuracy for particle Reynolds numbers from 185 up to 365. The sphere must be resolved with at least 24 computational cells per diameter to achieve velocity errors below 5%. The momentum exchange method is found to be more accurate in predicting the streamwise velocity component whereas the partially saturated cells method is more accurate in the spanwise components. The study reveals that the resolution should be chosen with respect to the coupling dynamics, and not only based on the flow properties, to avoid large errors in the fluid-particle interaction.

A coupled lattice Boltzmann method and discrete element method for discrete particle simulations of particulate flows

“…For a very similar coupling approach to the one applied here, this has already been used and demonstrated in Ref. 27, and is thus not repeated here. However, we explicitly note here that these settling tests do not contain particle-particle or particlewall collisions.…”

“…To close this apparent gap and study whether algorithmic adaptations similar to the ones for the classical DNS approaches are required also for LBM coupling schemes, the present work presents an in-depth calibration and validation study of such a four-way coupled simulation approach. We employ the momentum exchange method to establish the fluid-particle coupling whose benefits in terms of accuracy have already been shown previously [27]. We develop an adaptive multi-relaxation time LBM to reduce the spurious density fluctuations that are inherently present in this coupling scheme [28].…”

Hydrodynamic mobility reversal of squirmers near flat and curved surfaces

“…This reproduces solutions to the Navier-Stokes equations on sufficiently large length and time scales, which we resolve. Our specific implementation using the waLBerla framework 76,77 and its application to the present problem are described in Ref. 78.…”

Dynamic Load Balancing Techniques for Particulate Flow Simulations

“…The fluid flow is computed via the lattice Boltzmann method and a non-smooth granular dynamics simulation accounts for the motion and collisions of the suspended particles. A coupling of these two approaches is established based on the momentum exchange principle which features geometrically fully resolved particle shapes [2,18]. This coupling is illustrated in Figure 2.…”