Experimental Investigation of Discharge Capacity of Labyrinth Weirs

A labyrinth weir is a structure designed to convey large flows at low heads by increasing the effective length of the weir crest with respect to the channel breadth. The crest shape is one of the most important factors which affect the discharge capacity for labyrinth weirs. It is found that the labyrinth weirs are hydraulically more efficient than the other normal weirs for higher discharge. The discharge over the labyrinth weir is same as an equivalent length straight weir for low head, whereas, with increase in head over the weir, the coefficient of discharge continues to decrease due to interference of jet and the weir capacity ultimately equal to that of the linear weir having crest length equal to the channel width.