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DOE OSTI · 1809178

Self-consistent, high-order spatial profiles in a model for two-fluid turbulent mixing

Morgan, Brandon E.
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Abstract

A Reynolds-averaged Navier-Stokes model is presented with the property that it admits self-consistent, high-order spatial profiles in simulations of two-fluid turbulent mixing layers. Whereas previous models have been limited by the assumption of a linear mixing profile, the present paper relaxes this assumption and, as a result, is shown to achieve much better agreement with experimental profiles. Similarity analysis is presented to derive constraints on model coefficients to enforce desired self-similar growth rates that are fully consistent with the high-order spatial profiles. Through this similarity analysis, it is shown that care must be taken in model construction, as it is possible to construct certain terms in such a way as to leave growth rates unconstrained. This model, termed the k-Φ-L-a-V model, is then applied in simulations of Rayleigh-Taylor, Richtmyer-Meshkov, and Kelvin-Helmholtz mixing layers. Overall, these simulations confirm that the expected growth parameters are recovered and high-order spatial profiles are maintained.

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71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICSKelvin-Helmholtz instabilityRayleigh-Taylor instabilityRichtmyer-Meshkov instabilityturbulent mixing

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Morgan, Brandon E.. 2021-07-22. Self-consistent, high-order spatial profiles in a model for two-fluid turbulent mixing. https://doi.org/10.1103/physreve.104.015107

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