Abstract
A simple correction model for “subgrid” lubrication force is proposed for fictitious-domain simulation of solid-liquid flow employing the Variable-density Implicit Volumetric forcing. The model is to compensate the unresolved lubrication force for gaps of few grid spacings between the solid surfaces, and is validated with the examination of velocity history and fluid force acting on spherical particles falling under gravity towards a plane wall. The peak particle Reynolds number is from 7 to 58, and relative density between the fluid and the solid is up to 2.9. Excellent agreements have been observed among the simulation results, the experimental ones, and predictions from an analytical model which consists of the lubrication force proposed by Cox & Brenner (1967), the added mass force proposed by Milne-Thomson (1968), and the history term proposed by Mei & Adrian (1992).
