Multigrid computations with the immersed boundary technique for multiphase flows
International Journal of Numerical Methods for Heat & Fluid Flow
ISSN: 0961-5539
Article publication date: 1 January 2004
Abstract
Multiphase flow computations involve coupled momentum, mass and energy transfer between moving and irregularly shaped boundaries, large property jumps between materials, and computational stiffness. In this study, we focus on the immersed boundary technique, which is a combined Eulerian‐Lagrangian method, to investigate the performance improvement using the multigrid technique in the context of the projection method. The main emphasis is on the interplay between the multigrid computation and the effect of the density and viscosity ratios between phases. Two problems, namely, a rising bubble in a liquid medium and impact dynamics between a liquid drop and a solid surface are adopted. As the density ratio increases, the single grid computation becomes substantially more time‐consuming; with the present problems, an increase of factor 10 in density ratio results in approximately a three‐fold increase in CPU time. Overall, the multigrid technique speeds up the computation and furthermore, the impact of the density ratio on the CPU time required is substantially reduced. On the other hand, the impact of the viscosity ratio does not play a major role on the convergence rates.
Keywords
Citation
Francois, M., Uzgoren, E., Jackson, J. and Shyy, W. (2004), "Multigrid computations with the immersed boundary technique for multiphase flows", International Journal of Numerical Methods for Heat & Fluid Flow, Vol. 14 No. 1, pp. 98-115. https://doi.org/10.1108/09615530410511658
Publisher
:Emerald Group Publishing Limited
Copyright © 2004, Emerald Group Publishing Limited