Numerical analysis of the effect of the duct geometry on the hydrodynamic performance of rim-driven thruster

Abstract

This paper studies the effect of the duct geometry on the hydrodynamic performance of rim-driven thruster (RDT) based on Computational Fluid Dynamics (CFD) method. The effect of the thickness of the duct, the radius of the leading edge of the duct and the geometry of the trailing edge of the duct on the thrust coefficient, torque coefficient and efficiency are investigated and analyzed. The conclusion shows the thrust coefficient increases with the thickness of the duct decreasing, however the torque coefficient increases with the increase of the thickness of the duct, so the efficiency increasing with the decrease of the thickness of the duct. On the other hand, the radius of the leading edge of the duct has no significant effect on the thrust coefficient of the RDT. However, the torque coefficient of RDT decreases with the increase of the radius of the leading edge of the duct, so the efficiency of RDT increases with the increase of the radius of the leading edge of the duct. A comprehensive comparison shows that the RDT 15-0.5 (the duct thickness is 15 mm, the ratio of the radius of the leading edge of the duct and the duct thickness is 0.5) has the best hydrodynamic performance among the investigated RDT models in this work.