轴向超声速通流串列构型弦长比对气动性能影响的数值研究

To avoid blade flutter caused by the incoming flow with a high Mach number and a large incidence angle, the tandem blade technology is introduced into the Supersonic Through-Flow Fan (STFF) cascade, and the preliminary two-dimensional tandem modification and aerodynamic performance are studied. A detailed comparative study on the effect of chord length ratio for the front and rear blades of tandem blades is conducted through numerical simulation. The results show that the key factor affecting the aerodynamic performance is the impingement point of the leading edge shock on the pressure side of the rear blade. Under the conditions of this study, total pressure loss drops with decreasing in the chord length ratio. When the chord length ratio decreases from 0.99 to 0.43, the total pressure loss with a camber angle of 15° is reduced by 27% at design incidence while one with a camber angle of 30° is reduced by 38%. Further study shows that it is effective to reduce the loss by reducing the chord length ratio to control the rear blade leading-edge shock impingement location on the suction side and it is easier to achieve a reduction in the loss for a tandem blade with a small camber angle than that with a large camber angle.