Ship noise measurements are subject to relatively large variations that should be considered when these data are used. For modern naval ships operating at high speeds, propeller cavitation is the dominant source of radiated noise. This paper examines the variability of the broadband component of propeller cavitation noise based on statistical analysis of repeated measurements for several ships and propellers and on a conceptual model of the measurement process. Confidence intervals are determined for measured noise spectra and correlations are sought between the variability and certain important parameters. To explain these results, a number of phenomena are discussed that affect either the sound transmission properties of the water, the measurement procedure, or the acoustic source strength of propeller cavitation. (fr)
Variability of Ship Noise Measurements
1988
42 pages
Report
No indication
English
Marine Engineering , Acoustics , Acoustic measurement , Naval vessels , Ship noise , Broadband , Cavitation , Cavitation noise , Confidence limits , High velocity , Intervals , Mathematical models , Propeller noise , Marine propellers , Radiated noise , Sound transmission , Sources , Spectra , Statistical analysis , Level(Quantity) , Foreign technology
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