Impact of fouling on aerodynamic performance of centrifugal compressor impeller

Based on the fouling modeling of the centrifugal impeller blade through a three-dimensional nonuniform surface roughness map, detailed CFD simulations are performed to investigate the aerodynamic performance and flow fields of both clean and fouled impellers. The sensitivity analysis is conducted to find out the most important contaminated region causing the performance degradation. The results show that the fouled impeller has significantly reduced polytropic efficiency and total pressure ratio than the clean impeller; as the flow rate increases, the performance degradation becomes more pronounced. With the sensitivity analysis, the most important contaminated region associated with the impeller performance degradation is located at the blade tip at the leading edge. This study can provide theoretical foundation for the robust optimization design for the centrifugal impeller.