HULL CLEANING SYSTEMS USING CAVIJET CAVITATING FLUID JETS: A FEASIBILITY STUDY

Motivated by concerns of energy consumption and environmental protection, new methods for removing fouling from ship hulls are being considered, both for commercial and naval craft. A report has been completed for MarAd by Hydronautics, Inc. which evaluates the suitability of the CAVIJET cavitating water jet method in cleaning actual ship hulls. This follows as earlier first phase effort which successfully demonstrated the CAVIJET in the laboratory. Equipment for testing full-scale removal of fouling was developed and used in field trials on actual ship hulls in dry-dock. This same six-nozzle CAVIJET cleaning system was also used for underwater trials. Cleaning rates of over 500 sq m/hr (5,400 sq ft/hr) using pump pressures of 13.8 MPa (2,000 psi) or less were achieved compared with rates of about 90 sq m/hr (1,000 sq ft/hr) now achieved by conventional hand-held, sandsweeping devices. The practicality of the CAVIJET technology for commercial hull cleaning systems is, thus, clearly evident.