Analysis of Correlation Between Reaction and Flow Loss of Helium Compressor

Multi-stage axial helium compressor is one of the key components of helium turbine. High reaction design is usually used to enhance the enthalpy gain of a single stage to reduce the number of stages, but experience shows that high reaction often leads to a reduction in efficiency, so it is necessary to clarify the effect of reaction on flow loss when using high reaction designs. In this paper, the correlation between the profile loss, corner loss and tip leakage loss inside the compressor vane channel based on helium flow and the reaction degree is analyzed in detail using CFD method for helium compressors with different reactions. The results show that the profile loss of 100% reaction rotor and 50% reaction stator increases due to the high relative velocity. As the reaction increases, the high load in the rotor leads to the increase of the loss at the tip leakage of the rotor. And, the increase of the stator bending angel and spanwise differential pressure make the separation of the stator angle more serious. At 100% reaction, the tip leakage loss accounts for 53% of the rotor loss and the corner loss accounts for 60% of the stator loss. Based on the air compressor profile loss model, the profile loss model suitable for helium compressor is optimized through physical property analysis.