Unsteady Flow in Channel of Variable Cross Section

Abstract

Characteristic equations describing one-dimensional unsteady open-channel flow in an irregular channel are developed. The integration of these characteristic equations is presented and methods of approximation for the evaluation of the integrals involved in these characteristic equations are considered. The most promising of these numerical integration techniques are incorporated in computer procedures which are linked to form a complete program. This program is used in the modeling of the tidal motion in an inlet of the sea. The particular inlet chosen was one which contained large changes of cross-sectional shape along its length. The varying geometrical properties of the inlet, along its length, are included in the analysis by the preparation of tables of section properties with water level for a series of cross-sections. This information is read into the computer at the start of computations. Comparisons are made between computed water levels and actual field records.