分布式 SCS- CN 有效降雨修正模型建立及应用.

To solve the problem of the equation structure becoming more complex in the improved soil conservation service curve number (SCS- CN) model, a SCS- CN model with revised effective precipitation ( SCS- CN- REP) is proposed by introducing a revised coefficient after a comparison between the standard SCS-CN model and the improved model. Furthermore, for the complex area with low impact development (LID) in a city, a distributed SCS-CN-REP model was developed based on a hydrological response unit division in which the effects of the LID facility′s storage capacity on rainfall-runoff are also considered. Finally, taking the Shuangzi residential district in Beijing City as a study area, the rainfall-runoff is simulated and compared using the distributed SCS-CN-REP model. An analysis of the SCS- CN- REP model showed that when the revised coefficient is 1. 0, it is equivalent to the standard model, when the revised coefficient is smaller than 1. 0, it is equivalent to the improved model. In essence, the revised coefficient is a limit value of the runoff coefficient varied with the increase in precipitation. The distributed SCS-CNREP model application results demonstrated that the calculated runoff depth values are in good agreement with the measured values. The determination coefficients and Nash efficiency coefficient are 0. 91 and 0. 83 when the adopted value of the revised coefficient for permeable surfaces is 1. 0, and are 0. 92 and 0. 91 when the adopted value is less than 1. 0. The effects of the latter model are better than the former, indicating that the simulation effect can be effectively improved when the adopted value of the revised coefficient for permeable surfaces is less than 1. 0 in the distributed SCS-CN-REP model. [ABSTRACT FROM AUTHOR]