A study of parameter selection principle and internal flow mechanism in a multi-stage low-reaction axial flow compressor

A subsonic multi-stage highly loaded, low-reaction, boundary layer suction axial flow compressor design concept was proposed in this paper and its feasibility was studied from theoretical analysis. This design concept could greatly raise the single stage pressure ratio while keeping the compressor efficiency in a high level. The distribution principle of total pressure ratio and static pressure ratio in a multi-stage low- reaction compressor was studied as well as the selection principle of reaction, diffusion factor and other total parameters. Considering the design feature of this new type of compressor, the internal flow in a large geometry turning angle cascade was studied in order to establish the relation between geometry parameters and surface pressure distribution. The relation between surface pressure distribution and profile loss, trailing edge loss, etc was also studied in this paper. By using this design concept combined with the boundary layer suction method, a certain eleven stages axial compressor's count was reduced to seven. The numerical simulation was done in the last two stages which had typical flow characteristics. The simulation result proved that the multi-stage low-reaction axial flow compressor design concept was feasible.