PROPELLER CAVITATION AND INDUCED VIBRATION

Abstract

The demand to increase the efficiency of propellers has led to optimized propeller blade designs finding their way into the construction of high-powered commercial vessels, such as containers or LNG carriers and certain categories of passenger vessels, to mention but a few. It has become increasingly common to see the propeller tip rotate closer to the hull surface, sweeping the thick turbulent boundary layer attached to the hull, causing fluid structure interaction. At the same time, increasing the loading on marine propellers can lead to problems, such as noise, hull vibration, and cavitation. The degree above which, such phenomena as propeller cavitation can be the main perpetrators for intensive vibration during operation, their diagnosis and the solutions to mitigate this risk, such as the use of vortex generators, are discussed here, taking into account cost and longevity of the vessel as well as the involvement of classification rules.