The Effect of Sheet Cavitation on the Blade Spindle Torque of a Controllable Pitch Propeller

In order to help the design of a Controllable Pitch Propeller (CPP) and to prevent too high blade actuating pressure in the hub, a 5-bladed CPP model with modern skewed blade design has been used to measure its hydrodynamic blade spindle torque at various pitch settings. Tests have been carried out both in non-cavitating and cavitating conditions in the Deep Water Towing Tank (DT) and the Depressurized Wave Basin (DWB) at the Maritime Research Institute Netherlands (MARIN), respectively. This paper investigates the variations of the spindle torque as function of advance ratios and pitch settings. Emphasis is put on the effect of sheet cavitation on the blade spindle torque. Primary CFD calculations have been performed to calculate the blade spindle torque in open water, which are compared to the test results.