Numerical Simulation Of Three-dimensional Multi-medium Flow Problems

In this paper the real ghost fluid method(RGFM) is extended to the numerical simulat ion of three-dimensional mult i-medium flow problems. The construction of Riemann problems is presented for three dimensional problems at the interface. By solving the Riemann problems at the interface we can obtain the fluid states, which are then used to define the interface boundary conditions, such that the computation is thereby carried out as if in a single medium f low. In solving the three dimens ional level set equat ion which is used to track the interface, the fluid velocity at the int erface obtained from the Riemann solver is extended to the whole computational domain in order to avoid the bunching of the level set contours. With the help of the extension veloc ity we can obtain the uniformly distributed level set contour and more accurate interface position. Several three-dimensional problems are tested and the numerical results show that the presented algorithm is efficient and can capture the interface and complicated wave structures accurately.