溃坝洪水的二维算子分裂——特征线模拟

Two-dimensional Numerical Simulation of Dam Break with Characteristics Method Based on Space Operater Splitting

根据特征线法的基本原理,推导了一维浅水运动的特征线方程和相容性方程,构造了用于溃坝计算的显格式,模拟了一维矩形断面低坝全溃的洪水波演进过程,并基于算子分裂建立了相应的二维问题特征线数值格式,对瞬间部分溃坝时二维洪水波的演进过程进行了数值模拟。得到的数值模拟结果表明,这种方法精度高,有较强的溃坝涌波捕捉能力,展示了溃坝波的运动特性,为溃坝引起的灾害预测和分析及防灾减灾等工程问题提供一种有效的数值模拟方法。

By using the method of characteristics, an explicit onedimensional numerical scheme of sudden break of a low dam with rectangle section is constructed. The scheme shows good shockcapturing results. Based on it, a twodimensional numerical scheme of dam break with space operator splitting is built. The 2dimensional numerical simulation results show good shockcapturing, too. The method of characteristics, are proposed for dam break. The higher accuracy and good shockcapturing capability of the method of characteristics are proposed for dam break also,and the method is effective.