van de Meent Jan-Willem, Morozov Alexander, Somfai Ellák, Sultan Eric, van Saarloos Wim
Instituut-Lorentz, University of Leiden, Postbus 9506, 2300 RA Leiden, The Netherlands.
Phys Rev E Stat Nonlin Soft Matter Phys. 2008 Jul;78(1 Pt 2):015701. doi: 10.1103/PhysRevE.78.015701. Epub 2008 Jul 7.
We present simulations of coherent structures in compressible flows near the transition to turbulence using the dissipative particle dynamics method. The structures we find are remarkably consistent with experimental observations and direct numerical simulations (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 nonlinear instabilities.
我们使用耗散粒子动力学方法对接近湍流转变的可压缩流中的相干结构进行了模拟。尽管马赫数相差几个数量级,但我们发现的结构与不可压缩流的实验观测和直接数值模拟(DNS)结果非常一致。层流的分岔是双稳态的,当流体变得更具可压缩性时,会向更高的雷诺数转变。这项工作强调了相干结构在湍流转变中的稳健性,并说明了基于粒子的方法再现复杂非线性不稳定性的能力。