珠江河口水动力一维、二维联解的有限元计算方法

Finite element method combining the 1-D and 2-D hydrodynamic modeling of the Pearl River outlets

该文应用有限元联解方法计算珠江河网与河口的整个水动力。仿照四点隐式差分法在每个一维单元内部形成独立的单元方程组,改进RMA有限元软件包实现河网一维数值模拟。借鉴弹性力学年中通过固结杆件与块体的连接结点实现两构件组合计算的思路,设计了珠江河网一维、河口二维水动力联解的有限元法,通过单元矩阵的构建、合并与叠加,形成整体方程组,实现整体求解的连接模式,有效地解决了不同形态流场的模拟问题。应用研究表明:该方法合理,计算结果较理想。

The combined solution of 1-D and 2-D model with the finite element method has been applied to the calculation of the hydrodynamic situation in the river network and the outlets of the Pearl River. Simulating a Preissmann weighted implicit four-point format, an independent equation group has been developed in each 1-D unit, and RMA finite element software has been revised in order to realize 1-D river network mathematical modeling. The idea in the elasticity that the consolidated bar and block are connected at the junction to calculate jointly with the finite element method, is used as a reference. The finite element method of joining 1-D river network model and 2-D river outlet model is designed and the unit matrix is set up, combined and superimposed before the integral equation is established. In this way the problem of simulating different flow fields is solved. The application study proves that this method is logical and the calculated result is satisfactory.