离心式压气机变工况模拟及轴向力变化机理分析

Simulation of Variable Working Conditions and Analysis of Axial Force Change Mechanism for Centrifugal Compressor

在相继增压系统切换过程中增压器轴向力的变化会严重影响其稳定性,以Garrett TBP4增压器的压气机端为研究对象,建立了压气机全流道计算域并划分多面体网格,设计7个工况,利用CFD研究了相继增压系统切换过程中的切换时间、切换转速、切换出口压力变化对压气机轴向力的影响规律,同时结合内部流场分析轴向力变化机理。结果表明:切换时间主要影响轴向力的突增时刻,切换转速幅值主要影响最终轴向力的大小,切换出口压力幅值主要影响轴向力突增与否;叶片轴向力受流场影响最大。

The change of axial force for supercharger during the switching of successive supercharging systems will seriously affect its stability.Taking the compressor end of Garrett TBP4 supercharger as the research object,the full-flow path calculation domain of compressor was established and the polyhedral mesh was divided,seven working conditions were designed,and the effects of the switching time,the switching speed and the switching outlet pressure change during the switching process on the axial force of compressor were researched with CFD software.Meanwhile,the axial force change mechanism was analyzed based on the internal flow field.The results show that the switching time mainly affects the moment of sudden increase of axial force,the switching speed amplitude mainly affects the final axial force,and the switching outlet pressure amplitude mainly affects whether the axial force suddenly increases.The blade axial force is affected the most by the flow field.