Characteristics of high-turning tandem stator in highly loaded small compressor

A redesigned high-turning stator was studied in a highly loaded small compressor with tandem blades. During three dimensional (3-D) stacking of the tandem stator, the appropriate positive bow was adopted to achieve the best relative location between the front and rear blades. Performance curves of the original and redesigned stages were obtained by 3-D steady numerical simulations at different conditions under the design speed. The results show that separation of the original stator near the casing has been weakened. The adiabatic efficiency increases by 3.5% approximately at the design point; the front blade withstands main variations of stator's incidence, and the stability margin also increases by 2%. The redesigned tandem stator can distribute the high-turning blade loading along the axial chord more uniformly, so it is beneficial for the flow control of the blade boundary layer.