An Improved Conservative Direct Re-Initialization Method (ICDR) for Two-Phase Flow Simulations

We introduce an improved conservative direct re-initialization (ICDR) method (for two-phase flow problems) as a new and efficient geometrical re-distancing scheme. The ICDR technique takes advantage of two mass-conserving and fast re-distancing schemes, as well as a global mass correction concept to reduce the extent of the mass loss/gain in two- and three-dimensional (2D and 3D) problems. We examine the ICDR method, at the first step, with two 2D benchmarks: the notched cylinder and the swirling flow vortex problems. To do so, we (for the first time) extensively analyze the dependency of the regenerated interface quality on both time-step and element sizes. Then, we quantitatively assess the results by employing a defined norm value, which evaluates the deviation from the exact solution. We also present a visual assessment by graphical demonstration of original and regenerated interfaces. In the next step, we investigate the performance of the ICDR in three-dimensional (3D) problems. For this purpose, we simulate drop deformation in a simple shear flow field. We describe our reason for this choice and show that, by employing the ICDR scheme, the results of our analysis comply with the existing numerical and experimental data in the literature.

Automated summary

The ICDR method combines two mass-conserving and fast re-distancing schemes, as well as a global mass correction concept, to reduce mass loss/gain in two- and three-dimensional problems. Through investigation on 2D benchmarks, the dependency of interface quality on time-step and element sizes was analyzed, and the effectiveness of ICDR was demonstrated visually and quantitatively. The performance of ICDR in three-dimensional problems was also examined, showing compliance with existing numerical and experimental data in drop deformation simulations.