Fluid-solid Coupling Numerical Simulation and Reliability Study of Pipeline Centrifugal Compressor Impeller
The centrifugal compressor is the key equipment of long distance natural gas pipelines and its impellers may have fatigue failure when suffer alternating load in the long term.Focusing on the geometric modeling of the full flow path of impellers in pipeline compressors,the paper conducts computational fluid dynamics calculations and finite element analysis of the solid stress field based on actual operating parameters by integrating aerodynamic loads onto the impeller through flow-structure coupling and obtains the stress distribution of the impeller under operating conditions ultimately.Utilizing simulation results and considering the material characteristics of the impeller,this study establishes a fatigue life calculation model,then estimates the parameters of the three-parameter Weibull distribution(η=1.001 9,β=536.88,γ=-0.900 1)using the maximum likelihood estimation method to account for the uncertainty in the impeller's fatigue life,and calculates the probability distribution and reliability curve of the impeller's fatigue life through Monte Carlo simulations finally.The results indicate that the reliability of the compressor impeller remains above 90%after reaching 1010 cycles under rated operating conditions,indicating an infinite fatigue life state.By utilizing the reliability curves of the impeller under different stress amplitudes,this paper achieves the life prediction of centrifugal compressor impellers under various operating conditions of pipeline compressor stations.
Compressor impellerFinite element analysisFatigue lifeReliability evaluation
万方数据
维普
