A 2-D HYDRODYNAMIC MODEL FOR THE RIVER,LAKE AND NETWORK SYSTEM IN THE JINGJIANG REACH ON THE UNSTRUCTURED QUADRANGLES  

作　　者：ZHANG Xi-bing HU De-chao WANG Min 

机构地区：[1]State Key Laboratory of Water Resources and Hydropower Engineering Science, Wuhan University, Wuhan430072, China [2]Yangtze River Scientific Research Institute, Wuhan 430010, China [3]State Key Laboratory of Hydroscience and Engineering, Tsinghua University, Beijing 100084, China

出　　处：《Journal of Hydrodynamics》2010年第3期419-429,共11页水动力学研究与进展B辑（英文版）

基　　金：supported by the Eleventh"Five-Year Plan" Science and Technology Program of China(Grant No. 2008BAB29B08);the National Key Basic Research Program of China(973 Program,Grant No.2007CB714100);supported by the Yangtze River Scientific Research Institute project(Grant No.CKSQ2010075)

摘　　要：The main river, the Dongting Lake and river networks in the Jingjiang reach of the Yangtze River constitute a complex water system, for which a full 2-D hydrodynamic model is established instead of the traditional 1-D or compound models for simulation of such complex systems, based on the latest developments of computer technologies and numerical methods. To better handle irregular boundaries and keep the computation cost well in a reasonable limit, unstructured grids of moderate scale are used. In addition, a dynamic boundary tracking method is proposed to simulate variable flow domains at different floods, especially, when the moderate scale gird can not describe flows in narrow river-network channels at low water levels. The t9 semi-implicit method and the Eulerian-Lagrangian Method （ELM） are adopted, which make the model unconditionally stable with respect to the gravity wave speed and Courant number restrictions. Properties and efficiency of the model are discussed, and it is concluded that the new model is robust and efficient enough for the simulation of a big, complex water system. Validation tests show that the simulation results agree well with field data. It takes about 0.96 h to complete the computation of a 76 d flood, which indicates that the model is efficient enough for engineering applications.The main river, the Dongting Lake and river networks in the Jingjiang reach of the Yangtze River constitute a complex water system, for which a full 2-D hydrodynamic model is established instead of the traditional 1-D or compound models for simulation of such complex systems, based on the latest developments of computer technologies and numerical methods. To better handle irregular boundaries and keep the computation cost well in a reasonable limit, unstructured grids of moderate scale are used. In addition, a dynamic boundary tracking method is proposed to simulate variable flow domains at different floods, especially, when the moderate scale gird can not describe flows in narrow river-network channels at low water levels. The t9 semi-implicit method and the Eulerian-Lagrangian Method （ELM） are adopted, which make the model unconditionally stable with respect to the gravity wave speed and Courant number restrictions. Properties and efficiency of the model are discussed, and it is concluded that the new model is robust and efficient enough for the simulation of a big, complex water system. Validation tests show that the simulation results agree well with field data. It takes about 0.96 h to complete the computation of a 76 d flood, which indicates that the model is efficient enough for engineering applications.

关 键 词：2-D numerical model river network unstructured grid SEMI-IMPLICIT Eulerian-Lagrangian Method （ELM） boundarytracking 

分 类 号：O35[理学—流体力学] TV131.2[理学—力学]