EXPERIMENTAL STUDY ON FLOW STABILIZATION IN AN ICE HARBOR TYPE FISHWAY

Experimental investigation has been done on flow stability in a pool of Ice-harbor type fishway. Flow discharge through the partition wall between pools can be expressed by sums of flow dischargesover weirs and that through submerged orifices. Flow discharge coefficients for both are determined experimentally for theadopted shape of the partition wall. The root mean square values of water height fluctuation in the pool and velocity fluctuation at the weir crest of the wall are introduced for stability indices. Stable flow condition for the pass of fish can be maintained within the range of designed flow conditions, when the ratio of orifice width to total channel width is equal to 0.24±0.04, which corresponds to the case when discharge through orifices is comparable to that over the weirs. To expand the effectiveness of the fishway for wider flow range, the partition wall having different crest height in the left andthe right side weirs is studied experimentally.