A non-oscillatory energy-splitting method for the computation of compressible multi-fluid flows

TL;DR

This paper introduces a new non-oscillatory energy-splitting conservative algorithm for simulating compressible multi-fluid flows, effectively reducing nonphysical oscillations at material interfaces.

Contribution

It develops a Godunov-based high-order scheme using the generalized Riemann problem for improved multi-fluid flow simulations under isobaric conditions.

Findings

Effective suppression of nonphysical oscillations at interfaces

Accurate simulation of shock-interface interactions

Demonstrated high performance in numerical experiments

Abstract

This paper proposes a new non-oscillatory {\em energy-splitting} conservative algorithm for computing multi-fluid flows in the Eulerian framework. In comparison with existing multi-fluid algorithms in literatures, it is shown that the mass fraction model with isobaric hypothesis is a plausible choice for designing numerical methods for multi-fluid flows. Then we construct a conservative Godunov-based scheme with the high order accurate extension by using the generalized Riemann problem (GRP) solver, through the detailed analysis of kinetic energy exchange when fluids are mixed under the hypothesis of isobaric equilibrium. Numerical experiments are carried out for the shock-interface interaction and shock-bubble interaction problems, which display the excellent performance of this type of schemes and demonstrate that nonphysical oscillations are suppressed around material interfaces substantially.