Propeller-induced vibration: experimental tests in atmospheric towing tank

Al-Taiby, Kareem (2022) Propeller-induced vibration: experimental tests in atmospheric towing tank. Masters thesis, Memorial University of Newfoundland.

[English] PDF - Accepted Version Available under License - The author retains copyright ownership and moral rights in this thesis. Neither the thesis nor substantial extracts from it may be printed or otherwise reproduced without the author's permission. Download (9MB)

Abstract

Ship’s propellers are main sources of onboard vibration that can have adverse effects on humans and machinery alike. A reliable design tool that allows the prediction of propeller induced vibration, in the early design phases of new constructions would help prevent damage or discomfort and reduce costs related to later modifications of the propellers. In an effort to obtain data on vibration generated by ship’s propellers, tests can be performed on a ship model in a tow tank. Self-Propulsion, Resistance and Bollard tests are established tests used to characterize the ship's hydrodynamics in a tow tank. Recently some researchers are investigating the possibilities to help understand the how the propeller design affects the vibration and vibration propagation to the ship body. One of the main problems with these tests is the separation of vibrational contribution of the propeller versus the fundamental frequencies of the ship model. In this work, experimental model tests were performed to evaluate the pressure fluctuations created by the propeller on a vessels structure. Methods used to perform these tests included Experimental Modal Analysis and Operating Deflection Shape, the latter performed during the hydrodynamic tests. The results show how pressure measurements can be influenced by structural vibration and thus the importance of identifying ranges of vibrational effects from the ship models’ structure during hydrodynamic testing to understand if structural vibrations need to be removed from the pressure sensor measurements to give an accurate representation of vibration effects due to the propeller.

Actions (login required)

View Item