To research the control of hub-corner stall in a compressor with stator hub gap

a 1.5-stage axial flow compressor was studied. The effects of integral hub gap and partial hub gap on the aerodynamic performance of compressor at low-operating point and design point were studied by three-dimensional numerical simulation method. The results show that the integral hub gap can restrain the hub-corner stall and improve the performance of compressor

because the energy source of the “tornado” vortex is weakened by the leakage flow

and the “tornado” vortex begins from the hub surface and ends at the suction surface

but the performance of compressor is reduced due to the leakage loss produced by stator hub gap at design point. And the partial hub gap is significantly better than the integral hub gap

with the position of partial hub gap moving backward

the performance of compressor is gradually improved at low-operating point

and the damage to the performance at design point is gradually reduced. For example

the mass flow rate of TAI2 scheme increased by 0.89kg/s and the efficiency increased by 1.25% at low-operating point

and the efficiency of design point remained unchanged. In addition

only when the partial hub gap increases to a certain size could the hub-corner stall be restrained by enough leakage flow.