MIKE3软件模拟温差异重流的网格划分比较研究  

Comparative Research on the Mesh Generating of Temperature Difference Induced Heterogeneous Flow with MIKE3

作　　者：郭维维 许红师 胡孜军 GUO Wei-wei;XU Hong-shi;HU Zi-jun(College of Water Science and Engineering,Taiyuan University of Technology,Taiyuan 030024,China;Changjiang Institute of Survey,Planning,Design and Research,Wuhan 430010,China)

机构地区：[1]太原理工大学水利科学与工程学院,太原030024 [2]长江勘测规划设计研究院,武汉430010

出　　处：《中国农村水利水电》2021年第6期25-29,37,共6页China Rural Water and Hydropower

基　　金：山西省水利科学技术研究与推广项目(TZ2019018);山西省高等学校科技创新项目(2019L0223)。

摘　　要：当温度分层型水库发生突发污染事故时,掌握水体的水动力和水温分布特性对判断污染事件的发展和指导决策具有重要意义。MIKE3软件可用于水库水动力和水温的三维数值模拟,为探讨该模型水平向网格剖分和垂向坐标系选取对温差异重流模拟的影响,基于物理模型实验结果,分别建立了三角形、矩形和三角形矩形拼接网格的数值模型,垂向分别采用σ坐标和σ-Z混合坐标两种形式。结果表明,MIKE3软件可有效模拟温差异重流沿床面运动的特性;当异重流主流方向较显著时,建议采用与主流方向一致的矩形网格进行计算区域离散;采用σ-Z混合坐标时可通过增加垂向分层数减弱床面阶梯近似的影响;对于温度分层界面、异重流主流方向与河床底面三者差异较大水体,建议在垂向采用σ-Z混合坐标形式。When sudden pollution accidents occur in temperature stratified reservoirs,it is of great significance to grasp the hydrodynamic and water temperature characteristics of water bodies to judge the development of pollution events and guide policy-making.MIKE3 software can be used for the three-dimensional simulation of reservoir hydrodynamics and water temperature.In order to explore further the influence of the model’s horizontal grid division and vertical coordinate system selection on the density flow,based on previous physical model experiments the numerical models of triangular,rectangular,and triangular-rectangular coupled grids are constructed.The σ coordinates and σ-Z mixed coordinates are adopted.The results show that MIKE3 software can effectively simulate the characteristics of temperature stratified density flow.It can be concluded that when the mainstream direction of density flow is very significant,it is recommended to use a rectangular grid to discretize the study area.The ladder approximation of Z-coordinate model can be effectively weakened by increasing the number of vertical stratifications.For water bodies with large differences in temperature stratifies interface,mainstream direction and the slope of riverbed,it is recommended to use σ-Z mixed coordinates in the vertical direction.

关 键 词：MIKE3 异重流 温度分层 Σ坐标 网格划分 

分 类 号：TV131.2[水利工程—水力学及河流动力学]