3种湍流模型模拟水下重力流的比较研究(英文)  

Comparative Study of Three Turbulence Models in Modeling Subaqueous Gravity Flows

作　　者：王春凌[1] 黄河清[1] 周扬屏[1] 郭丽娜[1] 

机构地区：[1]安徽工业大学建筑工程学院环境流体研究所,安徽马鞍山243032

出　　处：《安徽工业大学学报（自然科学版）》2013年第3期225-233,共9页Journal of Anhui University of Technology（Natural Science）

基　　金：国家自然科学基金面上资助项目(40972086;41172103)

摘　　要：运用最新文献记载的3种用于数值模拟水下重力流的湍流模型模拟同一组新的水下重力流的实验。实验数据不仅包括传统的各垂向剖面的速度、浓度,也含有对应剖面的湍流动能。结果表明:在所比较的3湍流模型当中,k-ε模型的模拟性能最好,而MY和k-l模型的模拟均在重力流的上部混合区域呈现过量的扩散。进一步分析表明,MY模型和k-l模型所采用的依据墙面距离定义的宏观长度尺度L尽管可适用于水下重力流底部的壁面边界层,但不适用于重力流上部的自由剪切层,因为重力流上部自由剪切层的湍流长度尺度和依据壁面距离定义的宏观长度尺寸完全不同。Three turbulence models used recently in numerical simulation of subaqueous gravity flows are implemented in simulating a new experimental data set containing not only vertical structures of velocity and concentration but also turbulent kinetic energy. The results show that turbulence k-e model performs relatively well among the three models in predicting the vertical structures of the velocity, concentration and especially turbulence kinetic energy. Both Mellor-Yamada （MY） and k-I models present an excessive diffusion in the upper mixing area. Further analyses indicate that the macro length scale L used in MY or k-l model is heavily depending on the distance to the wall, though it may function well in flows dominated by a bottom boundary layer, but not appropriate in the upper interface free shear area in which the proper turbulence length scale should be quite different from that derived from boundary lancer.

关 键 词：重力流 湍流模型 数值计算 长度尺度 

分 类 号：O357.5[理学—流体力学]