Sea-trial verification of air-filled rubber membrane for mitigation of propeller cavitation induced hull excitation. (1st December 2015)

• Record Type: Journal Article
• Authors: Lee, Jeung-Hoon; Lee, Kyung-Jun; Kim, Jin-Hak; Kim, Boo-Ki
• Is Part Of: Ocean engineering. Volume 110 Part A (2015)
• Page Start: 314
• Page End: 324
• Publication Date: 2015-12-01
• Subjects: Propeller cavitation -- Rubber balloon -- Sea-trial -- Full-scale measurement -- Destructive interference; Ocean engineering -- Periodicals; Ocean engineering; Periodicals; 620.4162
• DOI: 10.1016/j.oceaneng.2015.10.030
• Languages: English
• ISSNs: 0029-8018

Abstract

Abstract: At a certain frequency, an air-bubble excited by an acoustic wave produces a destructive interference, which plays a vital role in mitigating propeller cavitation induced pressure fluctuations on ship׳s hulls. By taking advantage of the acoustically transparent nature of rubber material, previous effort proposed employing an inflatable air-balloon so that the destructive interference could be implemented without any energy consumption. For its verification in a full-scale ship, this paper presents sea-trial measurements with the following major contribution. To inflate the balloon to the design size, and to keep the volume constant despite draught changes, a parametric relation is proposed by a semi-analytical method incorporated with the ideal gas law. This scheme is exploited in the full-scale measurements to attain a noticeable hull vibration reduction of 65% at the exciting frequency of interest. Finally, this simple device is expected to be an inexpensive alternative for resolving vibration issues that arise from propeller cavitation. Highlights: Full-scale measurement with air-balloon has recorded 65% reduction of hull-vibration. Inflation method for the balloon is presented by a use of the ideal gas law. The simple device is expected as an inexpensive alternative for the propeller cavitation related vibration issue.