開水路における流量測定法に対する遷移流特性の適用について

Abstract

By means of the application of the geometric theory of ordinary differential equations tothe steady behaviour of an open channel flow, a functional diversity of control structuresin hydraulic behaviours is classified as a saddle point, which induces the transition fromsubcritical to supercritical, and as nodal and focal points, at which the flow changes its flowregime from supercritical to subcritical.The basic principle of hydraulics in the discharge measurement by various types of con-trol structures is thus furnished by the transitional behaviours of flow over control structures.The first part of this paper presents the rather rigorous proof of Btiss' and generalizedJaeger's theory on the critical depth theory as a function of discharge and depth. Thesecond part deals with some hydraulic characteristics of control structures like overflowspillways, a round crested weir and a Parshall flume, as devices for the discharge measure-ment of open channel flows.