摘要
针对某型弹用涡扇发动机振动超标问题,建立了一维有限元梁模型进行仿真与模拟,结合实际试车数据进行了故障分析和仿真,验证了故障原因在于工作转速内存在临界转速,在较大的不平衡力作用下,松动故障被激发。针对机匣加速度信号,研究了不对称刚度模型下松动故障的冲击特征,发现了松动故障所引发的机匣加速度时域波形特征的不对称性以及频谱中出现倍频特征,与实际弹用涡扇发动机试车数据非常一致。结果表明:振动故障是由于支承刚度不足,导致在临界转速附近出现松动故障。
Certain missile turbofan engine vibration was over standard , so a one-dimensional finite element beam model was established to simulate .The data from test were combined for fault analysis and simulation ,which was verified that there was critical speed at working speed .Loosen fault would be excited under larger unbalanced force.In this paper ,shock features of asymmetric stiffness model to casing acceleration signal were analyzed ,discovering that looseness would lead to asymmetrical features of acceleration time domain wave and multiple frequency features of frequency spectrum ,which was consistent with the data from test .Asymmetric stiffness looseness model was verified to be more fit for aeroengine looseness fault model .The results show vibration fault is caused by improper support stiffness ,which leads to looseness fault near the critical speed .
出处
《航空计算技术》
2014年第3期36-41,共6页
Aeronautical Computing Technique
基金
国家自然科学基金项目资助(61179057)
国家安全重大基础研究项目资助(613139)
关键词
航空发动机
整机振动
松动故障
故障分析
松动特征
aero-engine
vibration of the whole engine
looseness fault
fault analysis
looseness features
