A New Regularization of the One-Dimensional Euler and Homentropic Euler Equations

Gregory Norgard; Kamran Mohseni

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arXiv · 0907.0214

A New Regularization of the One-Dimensional Euler and Homentropic Euler Equations

Gregory Norgard·Kamran Mohseni

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Abstract

This paper examines an averaging technique in which the nonlinear flux term is expanded and the convective velocities are passed through a low-pass filter. It is the intent that this modification to the nonlinear flux terms will result in an inviscid regularization of the homentropic Euler equations and Euler equations. The physical motivation for this technique is presented and a general method is derived, which is then applied to the homentropic Euler equations and Euler equations. These modified equations are then examined, discovering that they share the conservative properties and traveling wave solutions with the original equations. As the averaging is diminished it is proven that the solutions converge to weak solutions of the original equations. Finally, numerical simulations are conducted finding that the regularized equations appear smooth and capture the relevant behavior in shock tube simulations.

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Gregory Norgard, Kamran Mohseni. 2009-07-01. A New Regularization of the One-Dimensional Euler and Homentropic Euler Equations. https://arxiv.org/abs/0907.0214

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