USING DIFFERENT TURBULENT VISCOUS MODELS TO INVESTIGATE HYDRODYNAMIC PERFORMANCE OF A DUCTED PROPELLER

Abstract

A ducted propeller, also known as a Kort nozzle, is a marine propeller fitted with a non-rotating nozzle. It is used to improve the efficiency of the propeller in some kinds of vessel, for example, fishing vessels, trawlers, push-boats and submarines, with heavily load or propellers with limited diameter. In this article, the authors employed three turbulent viscous models, RNG k-ε, k-ω SST and transition SST k-ω model, to investigate the flow field surrounding a propeller by using a commercial Computational Fluid Dynamic (CFD). The hydrodynamic performance of the ducted propeller system and effects of the different turbulent viscous models on the simulation results are also meticulously analyzed. The propeller, with the diameter of 3,65 m, angular velocity of 200 rpm, boss ratio of 0,1730, is selected to calculate, and the accelerating duct with the cross section of Naca 4415 profile is also studied. By using the CFD, geometry model of the ducted propeller is constructed, meshed, refined and computation. The results of the hydrodynamic performance of the ducted propeller has analyzed by using three turbulent viscous models to be shown. And then, from obtained simulation results, the hydrodynamic performances, pressure distribution, and coefficients of the propeller and duct has been also analyzed and discussed.