Flow Field Analysis and Surge Mechanism Discussion of Centrifugal Compressor in Low Flow

The flow scope,operating efficiency,safety and reliability of centrifugal compressor was influenced by the surge which was and still is the important and difficult problem in compressor research areas.The unsteady case of internal flow phenomena at designed speed in low flow was analyzed by numerical method and the unsteady flow characteristics before surging in all parts of centrifugal compressor were determined.That the performance of all parts declined near the surge condition was found by analyzing the steady simulation results.Finally,a new surge mechanism was proposed and discussed by comprehensively analyzing the steady and unsteady results.