Comparative CFD Analysis of PBCF Geometries

This paper gives a comparative numerical analysis of different propeller boss cap fin (PBCF) geometries using computational fluid dynamics (CFD) software. Previous experimental and numerical studies on PBCF applications are first summarized, highlighting their reported impact on ship propulsion and propeller efficiency. The incentive for study comes from industry demand and regulatory requirements for new builds to be more environmentally friendly and to reduce fuel consumption. A propulsion system with small ship propeller and PBCF has been studied, seven propeller cap and nine PBCF models are designed and evaluated through CFD open water test simulations. The numerical setup represents standard open water test conditions, and the results are compared against those of the initial propeller without PBCF. Initial propeller model is five blades fixed pitch propeller designed for 55m passenger ship. Thrust, torque, and propeller efficiency are evaluated and compared to analyse the impact of PBCF geometry on propeller performance. Also, detailed flow field analyses are performed in the region behind propeller to examine changes in vortex structure and velocity distribution induced by the fins. The numerical results provide insight into the interaction between PBCF design and propulsion behaviour.