Effects of cavitation during propeller ice interaction

Abstract

A series of trests with a 200 mm model propeller of the Canadian Coast Guard's R-Class icebreakers were conducted in the cavitation tunnel of the University of Tokyo's Department of Naval Architecture and Ocean Engineering. The experiments were conducted to examine the effects of cavitation on the hydrodynamic loads associated with the operation of an ice class propeller in the wake of a near by ice piece. Tests were conducted with the propeller operating in the wake of the simulated blockage over a range of cavitation numbers and advance coefficients. The blockage was mounted on an instrumented load cell and measurements were made of block load as the propeller blades passed into and out of a recess milled in the block. Cavitation duting propeller ice inrteraction results in a reduction of mean suction load on the ice block. Block load measurements indicate an increase in the oscillation about the mean value of the loads, with a variation in the phase of the loading with respect to blade position as compared to atmospheric results.NRC publication: Ye