Numerical Investigation on the Propagation Characteristics of Rotating Stall and Surge Pressure Disturbances in Pipeline System

Centrifugal compressors and pipeline systems operate as integrated units in industrial applications. At low flow rates, centrifugal compressors are prone to two distinct instability phenomena: rotating stall and surge. These instabilities generate pressure disturbances that propagate through the connected pipeline system, influencing its flow dynamics. This study utilizes numerical simulations based on the element-based finite volume method to examine the propagation characteristics of pressure disturbances, with the goal of uncovering the mechanisms behind experimentally observed pressure fluctuations. The results reveal that pressure disturbances associated with the rotating stall, characterized by specific frequencies, originate in the compressor and propagate downstream through the pipeline, gradually dissipating due to flow losses. In contrast, surge-induced pressure disturbances excite resonance within the pipeline system, causing widespread flow instability. The distinct propagation mechanisms of these two phenomena provide a novel approach to identifying centrifugal compressor instabilities and enhancing system diagnostics.