Abstract:

Underwater high speed target counter-rotation propeller always works at cavitation condition, the cavitation noise line-spectrum is due to the interaction between fore and aft propeller, and the interac- tion between the fore or aft propeller and wake of the ship. According to the acoustic analogy equation of Goldstein and making vacuole as one part of propeller, the academic prediction of counter-rotation propel- ler cavitation line-spectrum frequency is presented. The far field sound pressure expression of monopole sound source is deduced, and the line-spectrum prediction frequency is gained. The counter-rotation pro- peller cavitation is numerically simulated using Schnerr-sauer cavitation model, RNG k-着turbulence mod- el and dynamic mesh model. The results shows that the predicted cavity shapes of DTMB4381 propeller agrees well with the experimental observation and numerical simulation result on open literature, and the counter-rotation propeller cavitation line-spectrum frequency is got by this method which agrees with the result of Academic prediction absolutely.

Key words: acoustics, counter-rotation propeller, cavitation line-spectrum frequency, academic predic- tion, numerical simulation