Research on Erosion Effect of Various Submerged Cavitating Jet Nozzles and Design of Self-Rotating Cleaning Device

Submerged cavitating jets can effectively remove marine organisms from ship hulls without damaging the surface paint. To enhance the cleaning efficiency of cavitating jets, the selection of an appropriate nozzle structure and the design of an efficient cleaning device are crucial. In this study, the submerged cavitation effect of different nozzles was analyzed by numerical simulation. The actual cleaning efficacy of the nozzles was confirmed through erosion experiments as well. The simulation and experiment showed that the shear nozzle, absent of a pre-shrinking section and featuring a spherical outlet connected to a diffusion cylindrical section, maintained stable erosion performance at a standoff distance of 30–50 mm. This erosion was primarily attributed to denudation caused by bubble collapse. Based on this shear nozzle, a self-rotating cleaning device was designed and manufactured. A test rig was also established to test the cleaning effect and some parameters of the cleaning device.