Research on the impact of rain ingestion considering s-shaped inlet distortion on the performance of a centrifugal compressor

Abstract To study the combined effects of engine rain ingestion and outlet distortion of the S-duct inlet on the performance of a centrifugal compressor, this research conducted numerical simulations with the M2129 inlet and a specific centrifugal compressor as the research objects. At the same operating point, under the inlet-compressor coupled simulation condition, the downstream guide cone of the compressor exerts a stagnation effect on the outlet cross-section of the inlet, resulting in a decrease in the Mach number in the central region. Under the rain ingestion state in the coupled simulation, water droplets undergo two stages of breakup along the flow path; meanwhile, the special structure of the S-duct inlet leads to their accumulation at the compressor inlet. Both inlet distortion and rain ingestion cause a decline in the compressor’s performance parameters.