导管螺旋桨瞬时尾部涡演化数值研究OA北大核心CSTPCD

The ducted propeller is one of the main propulsion devices for ships today.The duct can reduce the tip vortex effect and provide part of the thrust.The transient wake field and the power spectral density of the ducted propeller are calculated,the evolution of vortex volume,pressure and kinetic energy in the transient wake field of the ducted propeller is compared and analyzed by the detached eddy simulation method.The calculation results show that the accelerated duct enhances the circumferential flow around the propeller,which helps to recover the kinetic energy of the vortex and improve the propulsion efficiency.The duct can delay the tip vortex contraction,reduce the degree of contraction,and play a role in suppressing the tip vortex.The kinetic energy spectrum analysis of the wake field quantitatively describes the evolution of the wake vortex structure,and the grouping and pairing phenomena of the wake vortex structure are observed.The amplitude of the kinetic energy spectrum of the ducted propeller near the characteristic frequency is significantly reduced and the decay is accelerated.