Turbulent transport and mixing in the multimode narrowband Richtmyer-Meshkov instability

TL;DR

This study analyzes turbulent transport and mixing in the narrowband Richtmyer-Meshkov instability using data from four simulation algorithms, focusing on flow budgets and compressibility effects to aid model validation.

Contribution

It provides a detailed comparison of four implicit large-eddy simulation codes and examines flow transport budgets for Richtmyer-Meshkov instability.

Findings

Quantifies the importance of transport terms in the flow.

Assesses the role of compressibility and pressure-dilatation.

Provides data useful for validating LES and RANS models.

Abstract

The mean momentum and heavy mass fraction, turbulent kinetic energy, and heavy mass fraction variance fields, as well as the budgets of their transport equations, are examined at several times during the evolution of a narrowband Richtmyer-Meshkov instability initiated by a Mach 1.84 shock traversing a perturbed interface separating gases with a density ratio of 3. The results are computed using the `quarter scale' data from four algorithms presented in the \theta-group study of Thornber et al. [Phys. Fluids 29, 105107 (2017)]. The present study is inspired by a previous similar study of Rayleigh-Taylor instability and mixing using direct numerical simulation data by Schilling and Mueschke [Phys. Fluids 22, 105102 (2010)]. In addition to comparing the predictions of the data from four implicit large-eddy simulation codes, the budgets are used to quantify the relative importance of the terms in the transport equations, and the balance of the terms is employed to infer the numerical dissipation. Terms arising from the compressibility of the flow are examined in particular, i.e., the pressure-dilatation. The results are useful for validation of large-eddy simulation and Reynolds-averaged modeling of Richtmyer-Meshkov instability.