对转桨扇三维流场特性数值研究

Contra-rotating propfan （CRP） is the most critical aerodynamic component of open rotor engine, and its aerodynamic performance has a huge impact on performance of the whole engine. Numerical simulations of the three-dimensional flow field of CRP with different advance ratios were carried out. The internal flow field of CRP and its vortex system structure in the wake and slipstream characteristics were analyzed on the basis of the theories of compressor and propeller. Results show that the flow characteristics and performance of the rear rotor change more than that of the front rotor. The actual inflow angle of the CRP is affected by the hub boundary layer, the induced velocity and the suction effect. The dominant position of three effects can be determined according to the distribution of axial velocity at different spans. The tip vortex is the main cause of loss in the slipstream, meanwhile, the radial vorticity decays faster than the circumferential and axial vorticity. The slipstream of CRP affects 3.5 times of the blade height. The outflow of the rear propfan continues to accelerate until its static pressure achieves the ambient pressure, the length of acceleration area is about 5 times of CRP radius.