某型直升机发动机尾喷管前转接段模态分析

Mode Analysis of Reset Section before the Nozzle of Some Certain Type of Engineer of Helicopter

摘要:

某型直升机发动机出现的尾喷管裂纹故障主要发生在尾喷管前转接段焊缝周围。为分析故障原因,文章建立了该型发动机尾喷管结构的计算模型。对该型喷管整体结构进行了自由振动和模态分析,获得了该喷管模型的多阶自振频率和模态。将有限元分析结果和实验结果对比表明,两者所得的固有频率吻合性较好。

Abstract:

Small cracks appeared in some certain type of engine’s jet nozzle of helicopter recently, the trouble chiefly occurs around the reset section welding seam before the jet nozzle. In this paper, based on a jet nozzle structure in the engine, a calculation model was developed. The numerical results of free vibration frequencies and modes were also obtained through analyzing the integrated jet nozzle structure. Mutual comparison showed that the results of FEA estimation were in good agreement with those of testing.