Abstract
A simple and practical VOF (volume-of-fluid) method is proposed, based on a continuous approach. A profile of the VOF function is approximated by a hyperbolic tangent function which is smoothly distributed across the transition region. A continuous approach with a smoothed interface avoids a difficulty to calculate the derivative values of the VOF function due to its discontinuity. Moreover, the analytical or numerical integration is able to be adopted in a flux calculation that enables a coding with a few IF-THEN types of conditional statements even if the interface is given as a curved surface. In this research, a validation test in the advection equation is carried out, moreover in the Navier-Stokes equations, a single rising-bubble problem is performed.
