离心压气机叶轮多场载荷与应力分析

Multi-Field Load and Stress Analysis of Centrifugal Compressor Impeller

建立了流固耦合计算模型,研究了离心压气机叶轮的离心载荷、热载荷、气动载荷及相应的应力。针对有蜗壳的整周离心压气机模型,采用单向稳态流固耦合的方法,分析了气动载荷、热载荷和相应的应力在周向上的不均匀性,讨论了柱坐标系下叶轮各部位主要的应力分量以及应力形成机理,定量分析了各场应力的占比,最后对比了多工况下各场应力比例关系。结果表明:气动载荷及应力在周向上的不均匀性较大,压力面正对蜗舌的叶片气动应力较大,且沿逆旋转方向叶片的气动应力不断减小;不同载荷作用下,叶轮各部位的主要应力分量有所不同;不同工况下,各场应力占比基本一致,离心应力均占据主导地位,其次为热应力,气动载荷的影响最小。

The fluid-solid coupling calculation model was established,and the centrifugal load,thermal load,aerodynamic load and corresponding stress of centrifugal compressor impeller were studied.For the model of full-cycle centrifugal compressor with a volute,the unidirectional steady-state fluid-solid coupling method was used to analyze the non-uniformity of aerodynamic load,thermal load and corresponding stress in the circumferential direction.The main stress components for each part of the impeller in the cylindrical coordinate system and the stress formation mechanism were discussed.The proportion of stress in each field was then quantitatively analyzed.Finally,the ratio of each stress field under multiple working conditions was compared.The results show that the aerodynamic load and stress have greater unevenness in the circumferential direction,the aerodynamic stress of blade with pressure surface facing the tongue is greater,and the aerodynamic stress of blade decreases in the reverse rotation direction.The main stress components for each part of the impeller were found to be different under different loads.Under different working conditions,the proportion of each stress field is basically the same.The centrifugal stress has a dominant influence,followed by the thermal stress and then the aerodynamic load.