Systematic cavitation tunnel tests of a Propeller in uniform and inclined flow conditions as part of a round robin test campaign

• Assessment of shaft inclination on propeller efficiency, cavitation and noise.
• Cavitation tests to collect scarce data for the shaft inclination effect on noise.
• The inclination of the propeller shaft is found to be causing earlier inception.
• Different kind of cavitation observed to have different noise signatures.
• Round Robin tests will reveal relative merits different testing facilities.

The effect of shaft inclination can induce important unsteady hydrodynamic phenomenon usually associated with small and high-speed craft. This paper presents systematic cavitation tunnel tests with a 214 mm diameter model propeller of a catamaran research vessel. The propeller is subjected to uniform and inclined flow conditions, to investigate its efficiency, cavitation and underwater radiated noise characteristics. The experiments were conducted in the Emerson Cavitation Tunnel of Newcastle University based on the starboard 5-bladed right-hand propeller of the University׳s research vessel, The Princess Royal. In the paper the details of the tests and significant findings for the effect of the shaft inclination on the propeller efficiency, cavitation and underwater radiated noise characteristics are presented. A better understanding is sought in relation to the noise signatures of different types of cavitation.The systematic tests presented in the paper also have a long-term objective, being the first of an organised round robin test campaign that is being currently undertaken by the members of the Underwater Noise Community of Practice (CoP) of Hydro-Testing Forum (HTF). This long-term objective is to repeat similar tests in the different facilities of all CoP members to reveal the relative merits of their testing facilities for underwater noise investigations.