摘要

The aft propeller of contra-rotating propeller (CRP) is able to recover the wake rotational energy of the forward propeller. CRP has advantages in terms of energy saving, efficiency, cavitation performance and stability. Propellers are generally operating in oblique flow. In order to study the influence of the oblique flow on the hydrodynamic performance of the contra-rotating propeller, based on the RANS equation and sliding mesh technology, the flow field of a CRP6 contra-rotating propeller is numerically solved on the Star-ccm+ at different oblique angles. The results show that the periodic fluctuations of thrust and torque of the contra-rotating propeller are significantly affected by the oblique flow, and new periodic phenomena appear; force on the forward propeller in all directions are larger than that of the aft propeller, thus strength of the front propeller needs to be considered seriously; the force amplitude of the aft propeller in all directions is larger than that of the forward propeller, thus the noise and fatigue problems of the aft propeller must be considered. The CRP6 is more energy-saving than a single propeller at small oblique angle, but is less energy-saving than a single propeller at large oblique angle.