ASSESSING THE IMPACT OF CAVITATION MODELS ON THE PERFORMANCE OF MOTORBOAT PROPELLERS: A NUMERICAL ANALYSIS

Abstract

This paper presents simulation of cavitating flows on a motorboat propeller and the performance changes brought by two cavitation models. K-ω SST was used as the turbulence model and effect of cavitation was introduced via cavitation models. The cavitation models are based on multiphase mixture model. Singhal cavitation model and Schnerr-Sauer cavitation models are some of the widely used cavitation models in literature. Both cavitation models were compared based on vapor fraction and performance parameters. The major difference in the two models is the inclusion of effects of non-condensable gases on Singhal cavitation model. The difficulty in setup and convergence of Singhal cavitation model has put forward other cavitation models as its alternatives. According to the results of this paper, both cavitation models show similar nature of cavitation in the propeller, with slight variation in performance parameters. If model parameters can accurately set according to properties of water, accuracy of these models can be further improved. Unless the effects of non-condensable gases are significant, the Schnerr-Sauer cavitation model is a good alternative to Singhal cavitation model to save computational costs.