Urans simulation of a partially submerged propeller operating under the bollard condition

Abstract

The performance of a partially submerged propeller under the bollard condition was assessed using numerical simulations based on URANS. The simulations were performed with varying propeller rotating speed and submergence depth. The propeller rotating speed was varied from 2 rps to 8 rps with the interval of 2 rps at the submergence depths of ℎ/R = 0.0, 0.5, and 1.0. Here, ℎ is the submergence depth from the free surface to the propeller shaft center and R is the radius of the propeller. The thrust and torque losses were compared with the thrust and torque in the deep water condition. The thrust and torque decreased rapidly with increasing propeller rotating speed. The thrust and torque ratios were compared with the empirical formula showing generally good agreement. The hydrodynamic characteristics around the partially submerged propeller were investigated using numerical simulations.