Two-equation and multi-fluid turbulence models for Richtmyer-Meshkov mixing
Kokkinakis, Ioannis W. and Drikakis, Dimitris and Youngs, David L. (2020) Two-equation and multi-fluid turbulence models for Richtmyer-Meshkov mixing. Physics of Fluids, 32 (7). 074102. ISSN 1070-6631
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Abstract
This paper concerns an investigation of two different approaches in modeling the turbulent mixing induced by the Richtmyer–Meshkov instability (RMI): A two-equation K-L multi-component Reynolds-averaged Navier–Stokes model and a two-fluid model. We have improved the accuracy of the K-L model by implementing new modifications, including a realizability condition for the Reynolds stress tensor and a threshold in the production of the turbulence kinetic energy. We examine the models in the one-dimensional (1D) form in the (re)-shocked mixing of a double-planar air and sulfur-hexafluoride (SF6) interface of the Atwood number |At| ≃ 0.6853. Furthermore, we investigated the models’ accuracy to RMI-induced mixing of a (re)-shocked planar-inverse chevron air–SF6 interface. Relevant integral quantities in time, as well as instantaneous profiles and contour plots, are used to assess the models’ accuracy against high-resolution implicit large eddy simulations. The proposed modifications improve the efficiency of the K-L model. The model is designed as a simple model capable of capturing the self-similar growth of Rayleigh–Taylor and Richtmyer–Meshkov flows. The two-fluid model remains more accurate but is also computationally more expensive.
Creators(s): |
Kokkinakis, Ioannis W. ![]() | Item type: | Article |
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ID code: | 73219 |
Keywords: | Richtmyer–Meshkov instability (RMI), Reynolds stress tensor, Reynolds-Averaged Navier– Stokes (RANS) model, two-fluid model, Physics, Physics and Astronomy(all) |
Subjects: | Science > Physics |
Department: | Faculty of Engineering > Mechanical and Aerospace Engineering |
Depositing user: | Pure Administrator |
Date deposited: | 15 Jul 2020 13:49 |
Last modified: | 21 Jan 2021 12:09 |
URI: | https://strathprints.strath.ac.uk/id/eprint/73219 |
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