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arXiv · 0807.1136

Coherent structures in Dissipative Particle Dynamics simulations of the transition to turbulence in compressible shear flows

Jan-Willem van de Meent·Alexander Morozov·Ellak Somfai·Eric Sultan·Wim van Saarloos
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Abstract

We present simulations of coherent structures in compressible flows near the transition to turbulence using the Dissipative Particle Dynamics (DPD) method. The structures we find are remarkably consistent with experimental observations and DNS simulations of incompressible flows, despite a difference in Mach number of several orders of magnitude. The bifurcation from the laminar flow is bistable and shifts to higher Reynolds numbers when the fluid becomes more compressible. This work underlines the robustness of coherent structures in the transition to turbulence and illustrates the ability of particle-based methods to reproduce complex non-linear instabilities.

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Jan-Willem van de Meent, Alexander Morozov, Ellak Somfai, Eric Sultan, Wim van Saarloos. 2008-07-07. Coherent structures in Dissipative Particle Dynamics simulations of the transition to turbulence in compressible shear flows. https://doi.org/10.1103/physreve.78.015701

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