河道一维非恒定流数值模拟深化研究

传统的河道一维非恒定流数值计算一般采用特征线法和以Preissmann方法为代表的有限差分法.特征线法计算精度比较高,但受时间步长的限制,用于河道一维非恒定流计算时计算效率却不太高.而Preissmann方法相比特征线法计算效率有所提高,但在求解过程中特征量的守恒性却没有做出相应要求.为了兼顾数值计算的效率和特征量的守恒,建立了基于有限体积法的河道一维非恒定流数值计算方法,并分别选取淮河干流洪水和史灌河洪水进行了验证计算,验证计算成果表明所采用的方法特征量守恒性较好,洪峰水位计算值与实测值吻合也较好,可用于河道一维非恒定流计算.

Further research of 1D numerical simulation of unsteady channel flow

In the traditional numerical simulation of unsteady channel flow,the characteristic method and the Preissmann method are usually used.It is excellent in keeping the balance of the quantity of water by using the characteristic method;but the computational efficiency need improved in nowadays.Though the Preissmann method has high efficiency,it can't keep the balance of the quantity of water.With the strong points of the methods reviewed ahead,a 1D numerical model of unsteady flow based on finite volume method is built.And the floods of Huaihe River and Shiguan River are used to check the accuracy of the model.The result shows that this model is really good in simulating the characters of unsteady flow and keeping the balance of the quantity of water.