Cavitation erosion in blocked flow with a ducted ice-class propeller

• Main Authors: Doucet, J. M., Bose, N., Walker, D., Jones, S. J.
• Format: Article in Journal/Newspaper
• Language: unknown
• Published: 1996
• Subjects: ducted propellers; cavitation; Arctic
• Online Access: https://nrc-publications.canada.ca/eng/view/object/?id=614a179c-ded4-43d0-aad4-b33c055780c1; https://nrc-publications.canada.ca/fra/voir/objet/?id=614a179c-ded4-43d0-aad4-b33c055780c1

Ships that operate in ice often encounter momentary increased propeller cavitation because ice pieces block the flow into the propeller. For ducted propellers, this additional cavitation is more significant than it is for open propellers; ice pieces may become lodged against and within the duct and subject the propeller to longer periods of increased cavitation due to the blocked flow. Associated with this blocked flow is the possibility of cavitation erosion on the propeller. An erosion study, using paint films, was conducted in a cavitation tunnel with a model propeller of the type fitted to the Canadian Marine Drilling Ltd. vessel MV Robert LeMeur. A simulated ice blockage was installed ahead of the propeller model and within the duct. Tests were carried out over a range of advance coefficients for various test conditions. The resulting types of cavitation were documented, the erosion patterns were photographed and comparisons between each test were made. NRC publication: Yes