A detailed investigation of aerodynamic performance of three low-speed rear axial compressor stage bladings with the aspect ratios: 0.75, 1.0 and 1.25 was carried out. The bladings of industrial type consist of rotor, stator and outlet guide vanes. The outer and inner diameters of the stage are constant. The hub/tip ratio is 0.871 and the outer diameter is 800 mm. Stage blading is followed by an annular diffuser with outlet chamber.
The effect of blade aspect ratio on compressor stage performance was also analysed with the use of straight cascade data. This data supported the test stage experimental results. We found that the effect of aspect ratio on stage performance is not remarkable in the considered range. There are some differences at off-design conditions. The lowest value of blading efficiency was obtained in the case with the lowest aspect ratio value.
Three inlet velocity profiles were modelled with the use of lengthened inlet annulus and a screen specially designed. It was found that there is a significant effect of inlet velocity profile distortion on rear compressor stage blading performance for all aspect ratios.
Aerodynamic characteristics of compressor stage blading with annular diffuser and outlet chamber were determined. During the investigation we also removed the outlet guide vanes. Therefore the effect of swirl and inlet velocity profile could be investigated.