Improved THINC/SW scheme for computing incompressible two‐phase flows

Abstract

Summary In this paper, we propose an improved tangent of hyperbola for interface capturing with slope weighting (THINC/SW) scheme for computing incompressible two‐phase flows with surface tension on fixed Eulerian grids. The new scheme possesses the following major new properties in comparison with the original THINC/SW scheme: (i) providing a simple and accurate approach for generating a smooth level set (LS) field from the discontinuous volume‐of‐fluid field, (ii) determining the interface slope from the cogenerated LS field, and (iii) evaluating the surface tension force by the cogenerated LS field. We verified the proposed scheme with the widely used advection benchmark tests and multifluid simulations. Numerical results reveal that the new scheme can not only improve the solution quality of interface capturing but also increase the accuracy of curvature estimates and suppress the parasitic currents.

A finite volume coupled level set and volume of fluid method with a mass conservation step for simulating two‐phase flows

“…The new updated value satisfies the mass conservation since H(𝜓 n+1 ) = 𝛼 allowing the accurate curvature calculation which is included in the surface tension force in momentum equation in Equations ( 25) and (31). The latter step is extremely important since it avoids the assumption that the interface position is located at the iso-surface contour 𝛼-0.5 (as in Kunkelmann and Stephan, 49 Albadawi et al, 36 Dianat et al, 48 Lyras et al 38 ).…”

“…Various studies have proposed different methodologies for improving mass conservation of the LS method 18,21‐32 . The particle level set (PLS) in Enright et al 18 is a semi‐Lagrangian level set method based on the advection of particles at both sides of the interface.…”

“…Various studies have proposed different methodologies for improving mass conservation of the LS method. 18,[21][22][23][24][25][26][27][28][29][30][31][32] The particle level set (PLS) in Enright et al 18 is a semi-Lagrangian level set method based on the advection of particles at both sides of the interface. Significant improvements were reported for mass conservation in the conservative level set method in Olsson and Kreiss, 22 Olsson et al 23 The authors, in addition to the advection of the level set function 𝜓, implemented a re-initialization step for the cells near the interface using the normal vector at the interface, n using a compressive flux 𝜓(1 − 𝜓)n. This correction step is applied for some iterations in steady-state 𝜓 for re-sharpening the interface.…”

A finite volume coupled level set and volume of fluid method with a mass conservation step for simulating two-phase flows

“…Various studies have proposed different methodologies for improving mass conservation of the LS method 21,22,23,18,24,25,26,27,28,29,30,31,32 . The particle level set (PLS) in 18 is a semi-lagrangian level set method based on the advection of particles at both sides of the interface.…”

“…( 25) and Eq. (31). The latter step is extremely important since it avoids the assumption that the interface position is located at the iso-surface contour α-0.5 (as in 49 36 , 48 , 38 ).…”