In a 1.5-stage transonic axial compressor

the controlling mechanism of bowed and swept blades was researched by 3-D numerical simulation when the compressor was working at different conditions. Results show that the combined scheme of sweepforward and positive bow is better than the combined scheme of sweepback and negative bow at the design speed

but its completely opposite at the part speed

because the controlling mechanisms of different bowed and swept schemes are different at the design speed and the part speed. The intensity and position of shock can be changed by the bowed and swept blades at the design speed

the same as the leakage vortex in the shroud gap and the spanwise C-shape pressure distribution; so the surge margin of compressor could be improved by combined action of three changed factors

but followed with the decrease of efficiency. However

the shock disappeared at the part speed

the reverse pressure gradient of the suction surface at the top of blade and the spanwise C-shape pressure distribution are changed

improving the aerodynamic stability of compressor and cutting down the efficiency.