Cavitation tunnel at SSPA

Research on predicting the risk of cavitation erosion on ship propellers

Damage to propellers due to cavitation erosion is a phenomenon that is becoming more frequent as propeller designers try to increase propeller efficiency. Energy-efficient propellers have usually some amount of cavitation at the design point and cavitation erosion damage may then occur, especially if the ship is operated off-design. An alternative design with a lower cavitation volume is not generally acceptable since this usually increases the fuel consumption. Our experts understand that there is a growing need to find new measurement methods to optimise propellers while at the same time minimising the risk of cavitation erosion. The measurement methods used today are too time-consuming to be used in more than a few operating conditions.

SSPA is collaborating on a project with other partners who are world leaders in their fields. The project will primarily develop an acoustic method that will allow model-scale tests to predict and quantify the risk of erosion at full scale, which will include the development and testing of measuring equipment to determine whether the acoustic emission technique is useful in a model scale and the extent to which the method correlates with full-scale observations. 

This new method will enable the fast and reliable scanning of a large number of operating conditions in order to map them, figure out which operational range is safe and what the risk of cavitation erosion is. The project will run until April 2019 with the partners Lloyds Register, Daewoo Shipbuilding and Marine Engineering, and the University of Southampton.