Flow of Layered Fluid over Broad Crested Weir

The case of two stable layers flowing from a reservoir through a contraction with a round crested weir at its minimum width is considered. The fluid is considered as inviscid and the flow gradually varied and the conditions under which a single layer may be separated from a two-layer system by having this lighter layer only flow over the weir are first obtained. The conditions under which the two layers continuously decrease from the reservoir to and downstream of the weir are then used to obtain the solution for the flow of the two stable layers. In both cases it is shown that the geometry of the weir and contraction is important. Experiments are carried out to verify the major conclusions of the theory.