Analysis on effect of shaft strut hydrofoil on anti-cavitation performance for surface ship

  Objectives  In order to improve the anti-cavitation performance of shaft strut on a surface ship,

  Methods  we study the front strut, compare the pressure distribution and anti-cavitation performance of the improved hydrofoil with those of the original hydrofoil at different attack angles of incident flows, and analyze the hydrodynamic performance of the improved hydrofoil at different flow rates and attack angles. We also predict the initial cavitation speeds of three types of hydrofoil according to the cavitation conditions, and verify the predicted values according to the calculation results.

  Results  The results show that the hydrodynamic performance and initial cavitation speed of the improved hydrofoil-1 have been significantly improved when compared with those of the original hydrofoil at the incident flow attack angles of 0°, 5° and 10°;the improved hydrofoil-2 has better anti-cavitation performance at the attack angles of 0° and 5°, while worse anti-cavitation performance at 10°;the initial cavitation speed predicted according to the pressure distribution is relatively close to the results based on the cavitation, which shows that it is feasible to predict the initial cavitation speed by this method when the accuracy requirement is not high.

  Conclusions  This provides a technical approach for vibration and noise reduction of a surface ship.