Experimental investigation on the hydro-acoustic characteristics of tandem cylinders

The investigation of the hydroacoustic characteristics of tandem cylinders has a great importance because they occur in a variety of maritime applications that include submarines, offshore structures, and seabed pipelines systems. Better understanding of the noise generation mechanism of tandem cylinders provides great contribution to reduce noise levels for many engineering applications. In this study, the hydroacoustic characteristics of tandem cylinders with same diameter were experimentally investigated for three different distance ratios at Reynolds number of 2.24x104. It was observed that the main peak spectrum becomes narrower as the distance ratio increases. The main peak frequency increases with the increase in distance ratio. Maximum sound pressure level has the highest value for the critical distance ratio of 3.0. When the distance ratio increases from 1.5 to 3.0, maximum sound pressure level significantly increases about 6 dB; but it decreases about 1 dB between the distance ratio of 3.0 and 6.0.