Numerical Investigation of the Effect of Trailing Edge Shape on Surface-Piercing Propeller Performance

Abstract

One of the main challenges in the development of surface-piercing propellers is to identify the effects of geometric parameters on the performance. The main geometric difference between SPP and conventional propellers is its blade section shape. The blade section is of super cavity type with a sharp leading edge and thick trailing edge. The geometry of this propeller is mostly designed experimentally, and comprehensive studies have not been performed to examine its parameters. Therefore, this research aims to investigate the effect of trailing edge shape on ventilation cavity development and SPP performance. The performance of a series of HL-tx propellers consisting of 6 propellers with different trailing edge shapes has been studied numerically. Numerical simulation of geometries was performed using URANS method coupled with the VOF method to capture the interface of fluids. The sliding mesh technique was also used to simulate the rotation of SPPs in transition mode. The results of the simulation method are in good agreement with the experimental data. As the results indicated, there was a 40% change in thrust and torque coefficients due to the trailing edge shape changes, which is a significant effect. However, changes in efficiency are about 7%. Meanwhile, the results revealed SPPs with a larger angle to the chord line and shorter height have better performance and ventilation cover behind the blade.