Hydraulic Character And Application For Labyrinth Weirs

The labyrinth weir is a special kind of practical and effective weir patterns. It can evidently increase the discharge for a given outflow width. So the labyrinth weir is particularly suited for use where the discharge structure need to enlarge the ability of outflow but the width is restrictedThe labyrinth weir could be divided into straight-labyrinth weir and curve-labyrinth weir in this paper. As for the straight-labyrinth weir, the flow pattern character, the discharge capacity and its effecting factors are discussed; the flow formula is deduced; a set of discharge coefficient formulas are given basing on the former study; and the efficiency is discussed. Then, a series of physical model experimentations are made to research the flow pattern character and the discharge capacity of curve-labyrinth weir. In this process, the major effect factors of outletcapacity are discussed and a new calculated method of discharge is given. At the same time, the research shows that curve-labyrinth weir precede straight-labyrinth weir in the sight of efficiency. Furthermore, an practical method about the labyrinth-crest spillway hydraulic design is brought out and the design example for reference is presented.