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| Prediction of High Frequency Noise Spectrum and Cavitation Inception Speed for Full Scale Propeller behind Submarine in Engineering |
| YANG Qiongfang1 WANG Yongsheng1 ＹＵＬｉａｎｇｑｉｎ3ZHANG Minming 2 |
| 1. College of Naval Architecture and Marine Power, Naval University of Engineering, Wuhan 430033;2. College of Electronic Engineering, Naval University of Engineering, Wuhan 430033 |
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Abstract For predicting the cavitation inception speed (CIS) and high frequency noise spectrum of full scale propeller behind submarine in engineering, combing cavitation multiphase simulation for model scale with semi-empirical formulas for high frequency noise spectrum prediction of the full scale propeller was used to investigate the CIS, cavitating noise spectrum curves and spectrum source level at the characteristic frequency 1kHz of the 7-bladed highly-skewed propeller behind full-appended SUBOFF submarine’s nominal wake. Validation of the cavitation simulation and tip vortex inception prediction were conducted by the calculated cavity pattern, area, and initial inception point of E779A propeller. Reasonability of the semi-empirical formulations was validated by the predicted noise spectrum of both USS212 submarine and the Agosta-80 submarine’s full scale propellers, and the precision was acceptable. The calculated results show that the CIS of the 7-bladed highly-skewed propeller is 12.8 knots under 16.8m water depth condition, and the spectrum level at 1kHz frequency for 6 knots speed is 101.7dB, which is 2.6 knots higher than that of the Agosta-80 submarine and 0.3dB lower for the spectrum level, so as to present its best noise performances. The numerical method proposed can be a productive approach to assess the full scale propeller’s critical speed and high frequency noise characteristics behind the submarine in engineering.
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Received: 15 June 2012
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2013, Vol. 32 
