Numerical simulation of dam-break flow impacting a stationary obstacle by a CLSVOF/IB method

Abstract

In this paper we develop a Coupled Level Set and Volume Of Fluid and Immersed Boundary (CLSVOF/IB) method, and apply it to simulating the interaction between dam-break flow and stationary obstacles. The projection method which adopts the second-order Adams–Bashforth algorithm is performed for solving the Navier-Stokes equations on a fixed staggered Cartesian grid. The Point Successive Over-Relaxation (PSOR) method is then employed to solve the discretized linear system of the Poisson pressure equation. For fluid-fluid interface treatment, the CLSVOF model is implemented using the Tangent of Hyperbola for INterface Capturing (THINC) scheme with the Weighted Linear Interface Calculation (WLIC), and the level set function which is a distance function is used to calculate interface normal vectors. For solid-fluid interface treatment, we adopt the direct forcing IB method which can be easily extended to three-dimensional simulations. The artificial momentum forcing term is applied at certain points in cells containing both fluid and solid, which imposes a velocity condition to drive the solid body motion. The proposed CLSVOF/IB model is used to simulate dam-break flow and its interaction with stationary structures, and the results agree well with numerical and experimental data in the literature.