Propeller Performance Analysis on the Modification of Trailing Edge Shape as Anti-Singing

Singing is one of the problems that occurs in the propeller. However, singing will not happen to every propeller. Singing occurs a lot in high-speed propellers and on propellers with wide and thin blade sizes. One of the ships that have high speed and wide propeller is fast patrol boat. To overcome this problem, modifying the trailing edge is one of the most commonly used methods. Sharpening the trailing edge is a way to reduce vortex shedding. However, modifying the trailing edge of the propeller will change the shape of the propeller, which can affect the performance of the propeller. Therefore, this study discussed about the effect of trailing edge modification as anti-singing on propeller performance. Propeller performance analysed with open water test simulation assisted by computational fluid dynamic based software. There are three sharpening model in this study, where the sharpening size in this study refers to Van Lammeren anti-singing design. The size of sharpening are 20 mm, 25 mm, and 30 mm, where 20 mm sharpening is the best modification to overcome singing according to flow analysis. The open water test simulation result shows that the modification of trailing edge as anti-singing can increase the average thrust coefficient 8.96%, average torque coefficient 7.88%, and average open water efficiency 1.29%.