A Study of Geomorphologic Instantaneous Unit Hydrograph

By using geomorphologic parameters, an instantaneous unit hydrograph model is developed to represent the hydrologic response of a drainage basin. The geomorphologic structure of a drainage basin is constructed according to Strahler's stream ordering system. The effective rainfall is transformed to direct runoff by using the geomorphologic instantaneous unit hydrograph which is obtained on the basis of flow paths of different order surface regions and streams of the drainage basin. The overland flow on the surface region is modeled by a linear reservoir. The channel flow of streams of different orders is divided into storage effect and translation effect. The latter effect is modeled by a linear channel, whereas the former is modeled by a linear reservoir. Based on a concept of service time, the constants of the linear reservoirs and linear channels are related to the geomorphologic parameters. The linear reservoir is a fictitious reservoir in which the storage is directly proportional to the outflow. The geomorphologic instantaneous unit hydrograph can be obtained by the convolution of the probability density functions of service times that water particles spent in traveling through different paths.

Name thesis:degree_name

Ph.D.

Level thesis:degree_level

Dissertation

Discipline thesis:degree_discipline

Civil Engineering

Grantor

University of Illinois at Urbana-Champaign

Year dc:date

2014

Author dc:creator

• Cheng, Bih-Ling Monica

• Engineering, Civil

Identifier

(UMI)AAI8218445

OAI identifier oai:identifier

oai:www.ideals.illinois.edu:2142/69903