Abstract
This paper deals with the characteristics of model parameters, P, K and Tl of the storage function model defined by the following equations,
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in which, Sl is the hypothetical storage depth of rain wa ter over a watershed considering the time lag Tl between rainfall excess re and flood runoff discharge Q.
First, the meanings of these parameters are examined by considering the similarity between this model and the kinematic runoff model. Moreover, the expressions for K and Tl are modified utilizing the Hack's law for engineering convenience.
Next, the statistical characteristics of these parameters obtained by applying a mathematical optimization technique of the 89 flood data in 22 watersheds are discussed through examination of the probability distribution of a parameter, and through comparisons between observed and simulated hydrographs and/or peak discharges. The usefulness of the modified expressions for K and Tl mentioned above, are also examined.
