The effect of inlet profiles on the repeatability in the single-stage compressor

A novel method has been proposed to design inlet gauzes in single-stage low-speed simulation compressor experiments. The aim is to investigate the method for designing inlet profiles and understand how they affect the repeatability of the compressor. Based on the inlet gauzes, the effect of the inlet profile on the compressor repeatability and its flow mechanisms was investigated by the experiments. The experiment results show that, for the single-stage low-speed compressor, as the inlet flow coefficient decreases, the loss and blockage near the rotor casing caused by the tip leakage flow are enhanced, resulting in an increase in the local absolute velocity and the total pressure. Meanwhile, the radial migration of the secondary cross flow in the stator is enhanced, leading to a thinner boundary layer at the stator outlet near casing region. Consequently, the flow capacity near the casing at the compressor outlet is enhanced with a decrease in the inlet flow coefficient. Given that the flow structure and the local loss of the compressor are not sensitive to the inlet profile at the near-choked condition, employing the inlet profile generated based on the compressor outlet profile at the near-stall condition can simulate the repeating stage environment accurately in the single-stage low-speed compressor experiment.