排灌机械工程学报2013，Vol.31Issue(4)：318-324,7.DOI:10.3969/j.issn.1674-8530.2013.04.009
导轴承刚度对水轮机轴系自振特性的影响
Influence of bearing rigidity on characterisitics of natural vibration of shaft system in hydro-turbine generating unit
摘要
Abstract
To study the characteristics of the lateral natural vibration of the main shaft system in hydroturbine generating unit,with the finite element method the main shaft system was discretized; and with energy method the dynamic equation was obtained.Based on simplified actual parameters,with MATLAB software,fixed frequencies,mode shapes and critical speed of rotation of the shaft system were calculated and influences on critical speed caused by changes in the guide bearing rigidity were analyzed.The results show that when only one guide-bearing rigidity is changed,up guide-bearing has little influence on critical speed; however,the down bearing and the water guide-bearing greatly affect the critical speed.There occurs a "saturated" phenomenon,that is to say,the critical speed remains unchanged when the rigidity reaches or exceeds a certain value.If the rigidity of the three guide-bearings is increasing simultaneously,the critical speed can be increased significantly.Change in the up guide-bearing has little effect on the modes in the first three orders; Change in the down guide-bearing and water guide-bearing will result in an opposite mode in a certain mode.It can be concluded that it is necessary to fully consider the effect caused by the guide-bearing rigidity in evaluating the critical speed of the shaft system.关键词
水轮发电机组/轴系/自振特性/临界转速/振型/导轴承刚度/饱和Key words
hydro-turbine generating unit/ main shaft system / characteristics of natural vibration /critical speed of rotation / mode of vibration / guide beating rigidity / saturation分类
能源科技引用本文复制引用
白冰,张立翔,赵磊..导轴承刚度对水轮机轴系自振特性的影响[J].排灌机械工程学报,2013,31(4):318-324,7.基金项目
国家自然科学基金重点资助项目(50839003) （50839003）
云南省自然科学基金资助项目(2008GA027) （2008GA027）
