小流域暴雨山洪水文模型与水动力学方法计算比较分析

针对小流域暴雨山洪精细模拟问题,提出了小流域时空变源混合产流模型,以小流域为单元构建了暴雨山洪分布式模拟模型,开发了可视化时空变源分布式水文模型软件FFMS和水动力学计算软件FHMS。以宝盖寺小流域场次暴雨洪水计算为例,分别采用水文学和水动力学方法计算了小流域暴雨山洪过程,并分析了两种方法的计算精度、效率、实用性等。案例研究结果表明:(1)水文与水动力学方法均可实现小流域暴雨山洪的模拟,模拟结果与实测基本一致;(2)对于无资料小流域暴雨洪水计算,水文学建模速度快,计算效率更高,水动力学方法建模和计算效率更低;(3)在复杂地形条件下暴雨洪水形成机理、演进过程模拟方面,水动力学计算结果更加精细和准确;在山区中小流域洪水预报预警方面,水文学方法更加实用。

Comparative analysis of hydrological and hydrodynamic calculation method for flash flood in small watershed

For the fine simulation of flash flood in small watersheds,this paper proposes a spatial and temporal source-variable mixed runoff model in small watershed, and builds a distributed simulation model of stormwater flash flood with small watershed as the unit, The visual distributed hydrological model software FFMS and hydrodynamic calculation software FHMS are developed. Taking the calculation of the storm flood in the small watershed of Baogai Temple as an example, the hydrological and hydrodynamic methods were used respectively to calculate the storm flooding process in the small watershed,and analyzed the calculation accuracy, efficiency and practicability of the two methods. The results of the case study show that:Fisrt, hydrological and hydrodynamics can simulate the stormwater flash flood in small watershed, and the simulation results are basically consistent with the actual measurements; Second, for calculation of storm floods in ungauged small watersheds,the hydrological modeling has faster modeling speed and higher computational efficiency compared with hydrodynamic method modeling;Third,when dealing with the formation mechanism and evolution process of storm floods under complex terrain conditions, the hydrodynamic calculation results are more precise and accurate; For flood forecasting and warning in small and medium watersheds in mountainous areas,the hydrological method is more practical.