An experimental investigation of the composite coating for marine propellers on cavitation characteristics and fouling release property

Abstract

Marine propellers with complex shaped surface could not satisfy hydrodynamics and have complex flow-structure interactions during running. While cavitation and marine organisms are two obstacles when ship propellers keep propulsion efficiency, many of them have been coated with fouling release coating to maintain propeller propulsion efficiency. In this paper, the introduction of the composite coating to marine propellers can not only effectively resist to cavitation erosion, but also be free from marine organisms. In the above context, tests for the cavitation characteristics of the composite coating were carried out. Composite coatings on the tool head for 40 h or hedging for 100 h had slightly loss of light with the cumulative weight loss less than 5 mg. Open water tests showed the composite coating did not significantly affect thrust and torque characteristics of model propeller. After the use on ship propellers for a period of 16 months, composite coating matched well only with minor damage on the leading edge, but none diffusion under the coating layer. And also marine organisms on blades of propeller could be washed away easily with high pressure water.