一维溃坝洪水波的数值模拟-时空守恒法

Simulation of One Dimension Dam-break Flow——Space-time Conservation Scheme

应用改进的时空守恒法对一维溃坝洪水波进行了数值模拟,从计算结果与分析解比较可知,该法能够很好地模拟溃坝洪水波,甚至对于下游为干河的情况,依然能得到满意的结果。而且,此方法精度高,有较强的溃坝涌波捕捉能力,可展示溃坝波的运动特性,为溃坝引起的灾害预测和分析及防灾减灾提供一种有效的数值模拟。

The new method of space-time conservation element and solution (CE/SE), developed by S. C. Chang, differs traditional numerical methods (finite-difference, finite-element, finite-volume, etc.). The CE/SE method treats space and time on the same footing, so that space and time are unified——a key characteristic that distinguishes the new method form other schemes. By the introduction of conservation element and solution element, both local and global flux conservation in space and time instead of in space only are enforced. Zhang Z C improved the method of space-time conservation element and solution element, which not only has all the features but also are simpler and easier to apply and have high accuracy and high resolution of discontinuities. The method of the improved scheme of space-time conservation element and solution element is used to simulate the 1-D unsteady open channel flow of sudden dam break. The calculation results are compared with analytic solutions. It is demonstrated that higher accuracy, good stability are obtained and good shock-capturing ability is shown.