INUNDATION MODEL IN THE REGION OF RIVER NETWORK SYSTEM AND ITS APPLICATION TO MEKONG DELTA

Abstract

A mathematical model is newly developed for inundating flow over a region in which a river network is extended. A 1-D mathematical model is applied to rivers, and the model is transformed into characteristics form to obtain a finite difference scheme. A finite leap-frog difference scheme for a horizontally 2-D model is applied to analyze the overland flow and inundation processes on the flood plain. Two schemes of 1-D and 2-D models are combined at several connection points by means of an overflow discharge formulae. The model is applied to the north-western Mekong delta in Vietnam, and characteristics of the inundation flow are discussed.