Non-Abrasive Propeller Cleaning System (NAPCS)

We propose to develop a propeller cleaning system using DYNAFLOW"s advanced cavitating and resonating waterjet technology. This non-abrasive technology generates cavitating microstructures in the jet flow at low jet pressures, thus avoiding problems with high jet impact pressures. It utilizes acoustic resonance, jet structuring, and swirl flow generation to enhance the cavitation intensity. The resulting bubble and vortex clouds collapse over the fouling and remove it. The DYNAJETS are effective at both very high and very low pump pressures depending on the fouling to remove. We propose to arrange the nozzles on rotating disks in an arrangement that allows self-induced disk rotation to increase coverage, simplify diver efforts, and clean the propeller surface efficiently and safely. A key strength of our approach is our fundamental and applied long term involvement with cavitation, erosion, and cavitating jet studies, which will enable us to develop an adaptable DYNAJETS tool where the jet operation conditions can be tuned to the types of fouling to optimize cleaning operation efficiency while protecting the underlying propeller material surface. In Phase I, the feasibility of such a DYNAJETS diver tool will be demonstrated, and the concept design will be developed through systematic experiments on fouled NAB plates.