基于凹槽结构的导管螺旋桨梢部流动研究

Inspired by the“casing treatment”in turbomachinery, a rectangular groove structure is applied to the inner surface of ducted propeller to reduce the strength of the tip vorticity and inhibit the cavitation of tip vorticity, which is expected to improve the hydrodynamic and cavitation performance. The unsteady numerical calculation of Ka4-70 propeller operating inside duct 19A, with or without grooves, was carried out by using computational fluid dynamics (CFD) method. The influence of groove structure on tip pressure, tip vortex strength, tip vortex structure and hydrodynamic performance of blades was studied. The results show that the groove structure can significantly change the tip vortex of duct propeller, weaken the strength of vortex, increase the minimum pressure at the tip of blade, and almost have no effect on the propulsion performance. The results provide a new solution for tip vortex control and vibration and noise reduction of the ducted propeller.