Viscous effects on cavitation inception on a two dimensional cylinder

Experiments were performed in a variable temperature cavitation tunnel with a two-dimensional circular cylinder as the test body to determine the relationship between cavitation inception characteristics of the test body and the change in the fully-wetted flow regime which occurs in the critical Reynolds number region. In the Reynolds number range considered (1.2 x 100,000 less than R sub d less than 8.5 x 100,000) three modes of limited cavitation occurred. At Reynolds numbers corresponding approximately to the subcritical range for fullywetted flow, cavitation inception was observed to occur in the wake downstream of the body. At Reynolds numbers broadly in the supercritical range for fully-wetted flow, up to a value of about 5.5 x 100,000, band type attached cavitation inception occurred across the downstream faces of the cylinder at about 110 deg from the upstream stagnation point. At Reynolds numbers greater than about 5.5 x 100,000, cavitation inception was of the attached spot type occurring at discrete spanwise locations.