横向裂纹对汽轮机转子扭振固有特性的影响分析

Analysis on the influence of transverse crack on the inherent characteristics of the torsional vibration of steam burbine rotor

随着发电事业的不断发展,汽轮发电机组和电网容量越来越大,轴系扭振问题日益突出,特别是当转子出现裂纹时,裂纹截面上的扭转剪应力会大幅增加。在机组运行过程中,若激振力频率和轴系扭振自振频率相近或重合,就会诱发共振,进而造成原有裂纹进一步加深或者因振动应力过大使得轴系上产生更多的裂纹,最后甚至会引起轴的断裂。因此,文章分析研究了裂纹分布在汽轮机转子不同部位对汽轮机转子扭振特性的影响,为全面揭示横向裂纹与汽轮机转子扭振特性的关系进行了有益的探索。

With the continuous development of the power industry,the turbogenerator and electrical network capacity is increasingly larger,and the problem of shaft torsional is increasingly prominent,and especially when crack occurs on the rotors,the trosional shear stress on the section of the cracks will be increased greatly.During the operation of the units,if the excitation force frequency exciting frequency and the frequency of the self-vibration of the shaft torsional vibration are similar or coincident,resonance will be induced to make original crack further deeper or more cracks occur on the shafting because of the excessive vibration stress,and even finally to lead to the fracture of the shaft.Therefore,this paper analyzes and studies the influence of the different position of the cracks on the steam turbine rotor on the torsional vibration of it,which proceeds a beneficial exploration for revealing the relation of the transverse crack and the characteristics of the torsional vibration of the steam turbine rotor.