This paper presents a class of high resolution KFVS (kinetic flux vector split-ting) finite volum methods for solving three-dimensional compressible Euler equa-tions with γ-gas law. The schemes are obtained based on the important connection between the Boltzmann equation and the Euler equations. According to the sign of the normal molecular velocity component at the surface of ally control volumes,one gives a splitting of the macroscopic flux vector, i.e. writes the macroscopic flux vector into the sum form of a positive flux and a negative flux. The initial reconstruction is applied to improve resolution of the schemes. Several numerical results are also presented to show the performance of our schemes.
This paper is about the positivity analysis of a class of flux-vector splitting (FVS) methods for the compressible Euler equations, which include gas-kinetic Beam scheme[8], Steger-Warming FVS method[9], and Lax-Friedrichs scheme. It shows that the density and the internal energy could keep non-negative values under the CFL condition for all above three schemes once the initial gas stays in a physically realizable state. The proof of positivity is closely related to the pseudo-particle representation of FVS schemes.
This paper is interested in a system of conservation laws with a stiff relaxation term arised in viscoelasticity. The properties of a class of fully implicit finite difference methods approximating this system are analyzed, which include maximum principles, bounds on the total variation, Ll-bounds, and L1-continuity estimates in term of some conserved physical quantity and this characteristic variables generated by difference schemes with proper initial data. These estimates are necessary for the existence of a bounded-total variation (BV) solution. Furthermore, we show that numerical entropy inequalities for some convex entropy pairs of the fully system hold.
This paper is to study the numerical approximations of the discrete-velocity kinetic equations (DVKE). We analyze the nonlinear stability, such as TV stability, L stability, for the semi-implicit difference schemes applied to DVKEs. Furthermore, the numerical entropy condition for a special difference scheme is also considered.