Further Studies of Ventilated Cavities on Submerged Bodies

Abstract

This report supplements an earlier report describing experimental studies conducted to determine the air requirements of ventilated cavities on hydrofoils and other submerged bodies in the vicinity of a free surface. Reentrant jet, trailing vortex, and pulsating cavities were observed.

In the present report, primary attention was given to extending an analysis of the type reported by Cox and Clayden and later extended by Campbell and Hilborne for predicting the air requirements of trailing vortex type cavities and for obtaining pertinent experimental data. It was shown that good agreement with the experimental data was obtained by both theoretical and semiempirical expressions.

Secondary attention was given to further verification of a correlation parameter previously derived for reentrant jet type cavities. The transition region between reentrant jet and trailing vortex cavities was also investigated. For some conditions, pulsating cavities were found in the transition region.