Unstructured conservative level-set method for interfacial transport processes on adaptive and fixed collocated meshes

Abstract

This paper reports advancements in the unstructured conservative level-set (UCLS) method for simulating two-phase flows with complex interfacial physics. The developed framework within the UCLS method addresses interfacial transport processes, including heat and mass transfer, variable surface tension, and liquid-vapor phase change. The transport equations are discretized using the finite volume method on three-dimensional collocated unstructured meshes. The UCLS method is utilized for interface capturing, while a multiple marker approach prevents numerical coalescence in bubbles and droplets. The fractional-step projection method solves the pressure-velocity coupling in the momentum transport equation. Unstructured flux-limiter schemes approximate the convective term, and the central difference scheme calculates the diffusive term. Verifications and validations focus on the thermocapillary migration of droplets using fixed meshes with mixed control volumes and hexahedral adaptive unstructured collocated meshes.

The principal author, N. Balcázar-Arciniega, as Serra-Hunter Lecturer (UPC-LE8027), acknowledges the financial support provided by the Catalan Government through this program. Simulations were conducted using computing resources allocated by the RES under the project IM-2024-1-0007 on the supercomputer MareNostrum V, at the BSC, Barcelona, Spain. The authors acknowledge the financial support of the MCIN/AEI/10.13039/501100011033 under the project PID2020-115837RB-100, Spain.

Postprint (published version)