Hydrological model calibrating method used for small watershed individual flood simulation

Abstract

The invention relates to a hydrological model calibrating method used for small watershed individual flood forecasting, comprising the following steps: collecting and treating data of a typical rainfall flood process; selecting a hydrologic catchment model with a mixed runoff generation mechanism; determining an objective function used for small watershed individual flood simulation; optimally selecting parameters for calibrating a hydrological model; and judging the applicability of the calibrated hydrological model to individual flood simulation. Aiming at defects in calibration of the hydrological model and by combining with the rainfall runoff generation characteristics of small watersheds in the north, a concentrated hydrological model with a mixed runoff generation mechanism is selected; by taking SCE-UA algorithm as basis and comprehensively considering three flood elements including flood peak, flood volume and flood hygrograph, parameters of the hydrological model can be calibrated by constructing a comprehensive objective function with variable weight; and on the basis of evaluating the calibrating effect of the hydrological model, a three-level judgment criteria comprehensively considering rainfall characteristics, drainage area and engineering requirements is provided, so that the calibrated hydrological model can better meet the requirement of flood forecasting ofsmall watersheds in the north.

Description

technical field [0001] The invention relates to the technical field of flood forecasting, in particular to a hydrological model calibrating method for small watershed secondary flood simulation based on a conceptual hydrological model. Background technique [0002] For small watersheds in semi-humid and semi-arid areas in the north, the duration and peak time of floods are generally short, and the floods fluctuate rapidly; The runoff pattern is reflected in the characteristics of both full-storage runoff and super-seepage runoff (for the general rainfall process in the northern basin, the rainfall intensity on the surface is greater than the infiltration capacity, and the super-seepage runoff is the main one. As the rainfall deepens, The formed soil midflow and underground runoff are mainly based on the full-storage runoff mode). Precisely because of its special characteristics of rainfall and runoff, flood forecasting for small watersheds in the north has always been diffi...

AI Technical Summary

Problems solved by technology

[0004] The present invention designs a hydrological model calibrating method for small watershed secondary flood simulation, and the technical problem it solves is that in the hydrological model calibrating process, no matter whether it is manual trial and error or automatic optimization method, there is no systematic Considering the particularity of flood forecasting in small watersheds, a unified objective function is generally used in the selection of the objective function and the evaluation standard for the calibration effect of the model is relatively simple

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