Effect of vane hub cap on hydrodynamic, cavitation and acoustic performance of propulsion system

Object and purpose of research. Effects of the vane hub cap are investigated regarding hydrodynamic, cavitation and acoustic performance of a ducted propeller as propulsion system. Materials and methods. In the work process two versions of the vane hub cap have been designed to take account of the wake field behind propeller. Experimental investigations of the propulsion system model with a smooth hub cap and designed hub cap are given. Additionally, positions of hub cap vanes with respect to propeller blades (in-between the blades or in wake of the blades) were studied. Main results. The thrust and torque coefficients as well as cavitation numbers were obtained, and the acoustic radiation was measured for the investigated propulsion system arrangements. Conclusion. Comparisons were made and conclusions drawn regarding the efficiency of vane hub cap application.