ADHESION PROOF DEVICE FOR CREATURE IN HEAD RACE

摘要

PROBLEM TO BE SOLVED: To prevent aquatic creatures from adhering by inclining inwardly the side walls of a head race and providing air-ejecting devices at the lower ends of the side walls. ;SOLUTION: A head race 1 is provided with side walls 2 inclined inwardly, a bottom wall 3, and a top plate 4 and is shaped to have a closed form. The head race 1 is installed below the water level and intake water 6 flows while filling the head race 1. An air-supplying pipe 8 blowing out air is provided along the longitudinal direction of the head race at the inside face of the connection part of the side wall 2 and the bottom wall 3. In the air-supplying pipe 8, a sintered alloy layer or the like having fine pores is formed for instance at the outer periphery of a pipe with holes to blow out fine bubbles. The air supply pressure is about 0.1-1.0 kg/cm2 G and the air volume is about O.1-1.O m3 per 1 m3 of the side wall. These fine bubbles rise along the inside face of the side wall to form an air layer 9 at the inside face of the side wall. Accordingly, this device prevents aquatic creatures from adhering on the side faces and the top plate of the head race.;COPYRIGHT: (C)2000,JPO