Spontaneous shrinkage of drops and mass conservation in phase-field simulations

JOURNAL OF COMPUTATIONAL PHYSICS

卷:223

Article

Yue, Pengtao ; Zhou, Chunfeng ; Feng, James J.

关键词: two-phase flow;    diffuse-interface method;    drop deformation;    drop shrinkage;    critical radius;   

DOI  :  10.1016/j.jcp.2006.11.020

来源: Elsevier

【 摘 要 】

In this note, we examine the implications of Cahn-Hilliard diffusion on mass conservation when using a phase-field model for simulating two-phase flows. Even though the phase-field variable phi is conserved globally, a drop shrinks spontaneously while phi shifts from its expected values in the bulk phases. Those changes are found to be proportional to the interfacial thickness, and we suggest guidelines for minimizing the loss of mass. Moreover, there exists a critical radius below which drops will eventually disappear. With a properly chosen mobility parameter, however, this process will be much slower than the physics of interest and thus has little ill effect on the simulation. (c) 2006 Elsevier Inc. All rights reserved.

【 授权许可】

Free