The entropy solutions of the compressible Euler equations satisfy a minimum principle for the specific entropy [10]. First order schemes such as Godunov-type and Lax-Friedrichs schemes and the second order kinetic schemes [6] also satisfy a discrete minimum entropy principle. In this paper, we show an extension of the positivity-preserving high order schemes for the compressible Euler equations...

We study numerical approximations of systems of partial differential equations modeling the interaction of short and long waves. The short waves are modeled by a nonlinear Schrödinger equation which is coupled to another equation modeling the long waves. Here, we consider the case where the long wave equation is either a hyperbolic conservation law or a Korteweg–de Vries equation. In the former...

The entropy solutions of the compressible Euler equations satisfy a minimum principle for the specific entropy [11]. First order schemes such as Godunov-type and Lax-Friedrichs schemes and the second order kinetic schemes [6] also satisfy a discrete minimum entropy principle. In this paper, we show an extension of the positivity-preserving high order schemes for the compressible Euler equations...

L∞ SOLUTIONS FOR A MODEL OF NONISOTHERMAL POLYTROPIC GAS FLOW∗ HERMANO FRID† , HELGE HOLDEN‡ , AND KENNETH H. KARLSEN‡ Abstract. We establish the global existence of L∞ solutions for a model of polytropic gas flow with varying temperature governed by a Fourier equation in the Lagrangian coordinates. The result is obtained by showing the convergence of a class of finite difference schemes, which...

We introduce a new technique for proving a priori error estimates between the entropy weak solution of a scalar conservation law and a finite–difference approximation calculated with the scheme of EngquistOsher, Lax-Friedrichs, or Godunov. This technique is a discrete counterpart of the duality technique introducedbyTadmor [SIAMJ.Numer.Anal. 1991]. The error is related to the consistency error ...

This paper is concerned with a posteriori error bounds for wide class of numerical schemes, $$n\times n$$ hyperbolic conservation laws in one space dimension. These estimates are achieved by “post-processing algorithm”, checking that the solution retains small total variation, and computing its oscillation on suitable subdomains. The results apply, particular, to solutions obtained Godunov or L...

We extend the weighted essentially non-oscillatory (WENO) schemes on two dimensional triangular meshes developed in [7] to three dimensions, and construct a third order finite volume WENO scheme on three dimensional tetrahedral meshes. We use the Lax-Friedrichs monotone flux as building blocks, third order reconstructions made from combinations of linear polynomials which are constructed on div...

In the high frequency regime, the geometrical-optics approximation for the Helmholtz equation with a point source results in an eikonal equation for traveltime and a transport equation for amplitude. Because the point-source traveltime field has an upwind singularity at the source point, all formally high-order finite-difference eikonal solvers exhibit first-order convergence and relatively lar...

Homotopy continuation is an efficient tool for solving polynomial systems. Its efficiency relies on utilizing adaptive stepsize and adaptive precision path tracking, and endgames. In this article, we apply homotopy continuation to solve steady state problems of hyperbolic conservation laws. A third-order accurate finite difference weighted essentially non-oscillatory (WENO) scheme with Lax-Frie...