Calculation of the Centrifugal Compressor Inlet Chamber and Impeller Taking into Account the Circumferential Flow Distortion

This paper presents the results of modeling the spatial flow in the first stage of a centrifugal compressor, including the inlet chamber. A case of significant influence of circumferential flow nonuniformity on the compressor’s stage characteristics and flow structure of a stage with increased local values of the Mach number is demonstrated. Obtaining a satisfactory analytical solution to this problem is not possible, while full-fledged unsteady simulations require significant computational and time resources. Significantly less resource-intensive methods of modeling pseudo-unsteady flow, such as the nonlinear harmonic (NLH) method, can be used for engineering evaluation. The resulting solution allows us to adequately assess the impact of the input device, take it into account when designing the flow path, and take the necessary corrective measures.