发表机构
AWE Nuclear Security Technologies（AWE核安全技术有限公司）
机构由 AI 辅助整理，请以论文原文为准。AI 中文总结
针对宽马赫数范围湍流，提出一种受CFL速度约束但独立于声速的半隐式全马赫数数值方法，采用有限体积离散，在高低马赫数及分层大气中验证，并与已有ILES模拟结果对比良好。
AI 中文摘要
隐式大涡模拟（ILES）是一种通过数值求解三维无粘欧拉方程来模拟高雷诺数湍流的成熟方法。这类湍流涵盖了广泛的马赫数范围，甚至在单个模拟中也是如此。例如，Richtmyer-Meshkov不稳定性模拟在后期演化过程中，会从高马赫数可压缩状态过渡到低马赫数准不可压缩状态。这些流动促使我们开发一种半隐式全马赫数数值方法，该方法受限于对应于流体速度的CFL稳定性约束，但与声速无关，并且可以在整个马赫数谱系中高效且准确地应用。此外，选择有限体积离散化以保持严格守恒，并确保对强激波的稳健且准确的捕捉。该方法在高马赫数和低马赫数状态下均得到了验证。同时，还针对存在重力的分层大气进行了验证，结果表明该方法适用于浮力驱动流动。我们将结果与先前发表的来自$\Theta$-group合作项目（Thornber等人，arXiv:1706.09991）的多模Richtmyer-Meshkov不稳定性ILES模拟进行了有利的比较。
英文摘要
Implicit Large Eddy Simulation (ILES) is a well established approach for modeling high-Reynolds-number turbulent flows by numerical solution of the inviscid Euler equations in 3D. These turbulent flows cover a wide range of Mach numbers, including within individual simulations. For example, Richtmyer-Meshkov instability simulations transition from a high-Mach compressible regime to a low-Mach quasi-incompressible regime during the late-time evolution. These flows motivate the development of a semi-implicit all-Mach numerical method, which is subject to a CFL stability constraint corresponding to the fluid velocity, but independent of the speed of sound, and can be applied efficiently and accurately across the whole spectrum of Mach numbers. Furthermore, finite-volume discretization is chosen to maintain strict conservation and ensure robust and accurate capturing of strong shocks. The method is validated in both high- and low-Mach regimes. Validation is also presented for stratified atmospheres in the presence of gravity, and the method is thus shown to be applicable to buoyancy driven flows. We present favorable comparison against previously published ILES simulations of multimode Richtmyer-Meshkov instability from the $Θ$-group collaboration, Thornber et al., (arXiv:1706.09991).
CommentsSubmitted to Journal of Computational Physics
