EROSION STUDIES DUE TO LIQUID JET IMPINGEMENT WITH PLAIN AND CAVITATING JETS.

Abstract

Experimental investigations were made on the characteristics of erosion resulting from the impingement of liquid jets ; six plain jets and four jets with cavitation inducers in a velocity range of 5 to 45 Infs. A detailed dimensional analysis of the several parameters governing liquid impingement erosion is presented. The growth of the jet size with stand-off distance for plain jets and the erosion characteristics due to variation in stand-off distance are also discussed. The normalized erosion rate increased with jet velocity and approached a constant value at higher jet velocities. The erosion rate decreased rapidly and then remained approximately constant with an increase in cavitation number. The erosion rate increased faster with frequency of impingement than with increase in jet velocity. A maximum value in peak erosion rate occurred around angles of impingement of 25 to 40 deg. The erosion rate-time curves for impingement of jets with cavitation inducers did not show the incubation an.' accumulation zones significantly. The cavity patterns obtained in the case of jets with cavitation inducers are similar to those reported in cavitation studies. The length and width of cavity increase with decrease in cavitation number.