高阶矩湍流模型研究进展及挑战

高阶矩模型是湍流模式理论研究中的难点和前沿. 自周培源先生首次建立一般湍流的雷诺应力输运方程起, 为了更精确的预测复杂流动, 人们从未间断过对高阶矩模型的研究. 尤其进入新世纪以来, 随着计算机硬件水平的飞跃和高精度数值算法的突破, 湍流模拟方法正由RANS向LES转变. 而无论对于RANS框架、LES框架还是两者混合, 高阶矩模式都是其中先进封闭模式的代表. 基于此, 本文对高阶矩模型的发展情况进行了总结, 重点包括高阶矩模型中各项的建模方式、尺度提供方程的演化历程和数值求解技术的关键需求. 然后, 通过几类典型湍流问题展示了其相对于传统涡黏模型的优势, 并且给出了部分CFD软件对高阶矩模型的集成情况. 最后对高阶矩湍流模型未来面临的挑战和发展的方向进行了展望. 

Progresses and challenges of high-order-moment turbulence closure

High-order-moment model is one of the focuses and frontier topics in the research of turbulence closure theory. Since Mr. Chou first established the Reynolds-stress transport equation in general turbulence, scholars have never stopped to study the high-order-moment model in order to predict the complex flow more accurately. Especially in the new century, thanks to the rapid development of computer hardware and the breakthrough of high-order numerical methods, turbulence simulation is in the course of turning from RANS into LES. In either RANS framework, LES framework, or the hybrid one, high-order-moment models are representative of advanced closure models. According to this, the paper gives a general review of the high-order-moment models. The focus includes the modeling approach of each source item, the evolution process of scale providing equations, and the research demand of numerical solution technology. Through several typical turbulence problems, their advantages over the traditional eddy-viscosity models are shown. Moreover, the integration of high-order-moment models in some CFD software is given. Finally, the future challenges and development direction of the high-order-moment turbulence model are prospected.