Shock Wave Structure for Argon, Helium, and Nitrogen

TL;DR

This study compares shock wave front thickness predictions for argon, helium, and nitrogen using Navier-Stokes and Quasi-gasdynamic models, validating against experimental data and analyzing convergence speeds.

Contribution

It provides a comparative analysis of NS and QGD models for shock wave structure in different gases, highlighting the accuracy and efficiency of QGD.

Findings

QGD and NS models agree well for argon and helium.

QGD results are closer to experimental data for nitrogen.

QGD converges faster to steady state than NS.

Abstract

We compare the thickness of shock wave fronts at different Mach numbers, modeled via Navier-Stokes (NS) and Quasi-gasdynamic (QGD) equations, with experimental results from the literature. Monoatomic argon and helium, and diatomic nitrogen, are considered. In this modeling a finite-difference scheme with second-order spatial accuracy is employed. For argon the density thickness calculated via QGD and NS models are in good agreement with each other, and with the experimental results. For helium QGD and NS results agree well with those from the bimodal model. For nitrogen, the QGD results are closer to the experimental data than NS results. The QGD-based algorithm converges to the steady state solution faster than the NS-based one.