轴向超音速来流下超音通流风扇叶型气动特性研究

To reveal the off-design performance of the axial supersonic flow fan (STFF) cascade, a numerical study on the influence of axial supersonic inflow on the aerodynamic performance of a typical STFF blade with a solidity of 3.32 was carried out. The results show that, on the whole, compared with the incidence angle, the inlet Mach number has less impact on the total pressure loss coefficient, static pressure ratio, load coefficient and exit flow angle. When the incoming Mach number increases from 1.58 to 2.36, the blade loading decreases slightly, while the total loss increases gradually. The variation of the total loss is mainly due to the change of the passage losses. Besides, compared to the shock loss and the bluntness loss, the viscosity loss is less affected by Mach number, and its variation accounts for about 20% of the total loss variation. The separation scale of the boundary layer on the blade suction surface is weakened with the increase of the incoming Mach number. This is because the intersection point between the pressure side branch of the leading edge shock and the adjacent blade suction surface moves downstream with the increase of inlet Mach number, resulting in a decrease in the shock angle and an increase in the Mach number ahead of the shock. However, under the combined effect of the two, the shock intensity is weakened.