Block-Structured AMR for Multi-medium Compressible Flows

In this research, THINC (tangent of hyperbola for interface capturing) (Xiao F. et.al, Int. J. Numer. Methods Fluids., 2005, 48(9): 1023-1040) coupled with GFM (Ghost Fluid Method) is proposed for numerical simulation of multicomponent compressible flows.

We develop an efficient AMR solver with high order schemes to solve the compressible multicomponent flows. The THINC/SW scheme is extended for sharp representation of the moving distorted material interface. A modified version of real GFM approach is applied to construct the Riemann problems on the interface and the solutions are used to compute the inter cell fluxes near the interface. Ghost states are approximated by the corresponding interfacial states. The level set method is also implemented with the GFM for comparison. To our knowledge, it is the first endeavor to apply the THINC scheme to the GFM simulations for multicomponent flows. A hybrid WENO scheme is adopted in which the WENO-Z is used only at the region containing discontinuities, while the high order upwind scheme with fixed stencils is used for other smooth areas. A smooth transition is considered to make the hybrid scheme robust. To decrease the computing cost, the proposed method is implemented using a blocked structured adaptive mesh. Parallel computation with dynamic load balance algorithm is also performed.