标题： 湍流解析积分模拟用于壁面受限流动 显示英文标题

标题： Turbulence-Resolving Integral Simulations for Wall-Bounded Flows

摘要： 湍流模型的物理保真度可以通过部分解析脉动来显著受益，但这样做通常会带来计算成本的显著增加。 为了在壁面受限流动的背景下探索这种权衡，本文引入了一个用于湍流解析积分模拟（TRIS）的框架，其目标是通过由速度和压力的瞬时法向积分定义的二维场，高效地解析最大的运动。 使用从纳维-斯托克斯方程中得出的动量矩积分方程，并采用相对简单的闭合近似，展示了在开放渠道（半通道）流动中TRIS的自维持湍流，具有定性上现实的大尺度结构。 直接数值模拟（DNS）的证据表明，这种方法可以在任意高的雷诺数下解析35-40%的雷诺剪切应力。 当前TRIS的实现可以在单个处理器上仅用约1分钟的时间模拟一个流动，即使在非常大的雷诺数下也能达到这种分辨率。 这里展示的当前概念验证TRIS结果依赖于参数调优，并且观察到与DNS频谱的一些定量差异，这促使正在进行和未来的努力，以开发基于物理的闭合方法，并扩展到更一般的流动配置，如浸没物体上的边界层。 显示英文摘要

摘要： The physical fidelity of turbulence models can significantly benefit from a partial resolution of fluctuations, but doing so often comes with a significant increase in computational cost. To explore this trade-off in the context of wall-bounded flows, this paper introduces a framework for Turbulence-Resolving Integral Simulations (TRIS) with the goal of efficiently resolving the largest motions using two-dimensional fields defined by instantaneous wall-normal integration of velocity and pressure. Self-sustaining turbulence with qualitatively realistic large-scale structures is demonstrated for TRIS on an open-channel (half-channel) flow using moment-of-momentum integral equations derived from Navier-Stokes with relatively simple closure approximations. Evidence from Direct Numerical Simulations (DNS) suggests that such an approach can resolve 35-40% of the Reynolds shear stress at arbitrarily high Reynolds number. The current implementation of TRIS can match this resolution while simulating one flow through time in ~1 minute on a single processor, even for very large Reynolds number. The present proof-of-concept TRIS results shown here rely on parameter tuning, and some quantitative differences with DNS spectra are observed, motivating ongoing and future efforts towards physics-based closures as well as extension to more general flow configurations such as boundary layers on immersed objects.