If you are experiencing problems downloading PDF or HTML fulltext, our helpdesk recommend clearing your browser cache and trying again. If you need help in clearing your cache, please click here . Still need help? Email email@example.com
This paper presents the experimental measurement of lift and drag as well as the determination of the onset of cavitation on rudders with leading-edge protuberances (tubercles) that are operating at low to moderate Reynolds Numbers in water. The leading-edge shape used for the rudders
in this study is derived from our earlier work concerning the analysis of the leading-edge morphology found on the pectoral flippers of humpback whales. While humpback whales do not swim at speeds that induce cavitation, engineered control surfaces based on this bio-inspired control surface
modification might operate in cavitation conditions. This point motivates our present work to investigate the onset of cavitation on small aspect ratio rudders with tubercles. Our findings are that (i) the presence of leading-edge tubercles accelerates the onset of cavitation, (ii) the tubercles
can modify the location of the onset of cavitation, (iii) the tubercle geometry has an influence on the rudder's hydrodynamic performance, (iv) for the lower Reynolds Numbers considered in this paper, the tubercles decrease lift and increase drag for angles of attack between 15 and 22 deg,
(v) for angles above 22 deg, rudders with tubercles generate more lift than smooth rudders, and (vi) for the higher Reynolds Numbers investigated, the difference in performance between the smooth and tubercled rudders diminishes, suggesting the existence of a critical Reynolds Number for a
given tubercle geometry beyond which tubercles have no significant effect on hydrodynamic performance.
Marine Technology is dedicated to James Kennedy, 1867-1936, marine engineer, and longtime member of the Society, in recognition and appreciation of his sincere and generous interest in furthering the art of ship design, shipbuilding, ship operation, and related activities. The Technical papers in this quarterly flagship journal cover a broad spectrum of research on the latest technological breakthroughs, trends, concepts, and discoveries in the marine industry. SNAME News is packed with Society news and information on national, section, and local levels as well as updates on committee activities, meetings, seminars, professional conferences, and employment opportunities. For access to Volume 47 Issue 2 and later, please contact SNAME