基于DEM的等流时法改进研究

How to Improve Isochronous Confluence Based on DEM

提出等流时单元的概念,对基于DEM的等流时流域汇流方法进行了改进。此方法不需要绘制等流时线,也不要求流域净雨是均匀的,且各单元的汇流时间可以变动,直接由各单元的汇流时间就可以计算出流域出口的流量过程。同时提出改进方法的模块化编程方法,给出调用接口,经在研究区伊通河中下游较大流域上的试用表明,该程序具有可推广性。

A new concept of isochronous cells was put forward.An improvement research was conducted on the concentration method of watershed overland flow.The hydrograph was got with the net rainfall of every DEM cell and the conflux time of every cell directly rather than traditional method of plotting isochronous-line in advance.In addition,unreasonable hypothesis of the previous research on it was smoothed over,in which the net rainfall is all the same on the watershed and isochronous line is immovable.According to current research situation,there isn＇t a modularized and practical program of isochronous cell method.To facilitate the popularization of this method,the modular programming method was provided.The feasibility of the program was proved in a case study of the watershed of the downstream of the Yitong river.