减小集总式水文模型洪峰相位差的方法

A method for decreasing flood peak phase difference of lumped hydrological model

采用集总式NAM水文模型模拟五道沟水文站以上集水区域的流量过程,选取1985—2010年洪峰流量最大的前9场洪水率定模型参数。模拟结果表明,洪峰存在系统性的相位提前,且调整模型参数的方式无法减小洪峰相位差。为获得合理的模拟结果,提出2种改进模型——错位加权生成面雨量的集总式NAM水文模型和同时刻加权生成面雨量的基于子流域的NAM水文模型。2种改进方法计算结果表明,峰值相位差减小,确定性系数和合格率提高。

Based on the NAM model, which is a lumped hydrological model, the discharge at the Wudaogou Hydrological Station was simulated. Nine flood events with the largest peak flows from the period of 1985 to 2010 were chosen to calibrate the model parameters. Simulation results show that peak flow appeared in advance systematically, and the flood peak phase difference could not be decreased by adjusting model parameters. In order to obtain reasonable results, two improved models are proposed： one is a lumped NAM hydrological model that does not change model parameters but deals with area precipitation by shifting time weighted, and the other is a NAM hydrological model, which is based on sub-catchments and deals with simultaneously weighted area precipitation. Calculation results of the two improved models show that the flood peak phase difference decreases, and the coefficient of determination and the qualified rate increase.