偏心对汽轮机隔板汽封泄漏流动特性的影响  

Influence of Eccentricity on Flow Characteristic of Steam Turbine Diaphragm Seal Leakage

作　　者：曹丽华[1] 李超[1] 李盼[1] 李勇[1] 肖斌[1] 

机构地区：[1]东北电力大学能源与动力工程学院,吉林吉林132012

出　　处：《润滑与密封》2016年第11期1-5,共5页Lubrication Engineering

基　　金：国家自然科学基金项目(51576036)

摘　　要：当汽轮机转子存在偏心时,隔板汽封间隙内的汽流激振力将发生变化,影响汽轮机组的安全运行。采用计算流体动力学软件,分析转子偏心工况下,某300 MW汽轮机高压缸第二压力级隔板汽封内汽流激振力的变化规律。结果表明:密封的周向压力近似呈余弦规律分布;随着偏心距的增加,隔板汽封内周向压力差逐渐增大;汽封间隙不变时,正向力、切向力和合力皆随着偏心距的增加而增加;在不同汽封间隙下,当转子偏心距相同时,间隙越小汽流激振力就越大。The which may affect in the diaphragm steam exciting force in diaphragm seal clearance changes with the eccentricity of steam turbine rotor, the safe operation of the steam turbine. Under the eccentric state, the change rule of steam exciting force seal of the second pressure stage of high pressure cylinder of a 300 MW steam turbine was analyzed by means of a computational fluid dynamics software.The results show that the circumferential pressure of the seal is a nearly cosine distribution.The circumferential pressure difference of the seal is increased gradually with the increasing of eccen- tricity.Under the same seal clearance, the normal force,tangential force and resultant force are all increased with the in- creasing of eccentricity.Under the different seal clearances and the same eccentricity ,the smaller the seal clearance is ,the larger the steam exciting force becomes.

关 键 词：汽轮机 隔板汽封 汽封间隙 汽流激振力 

分 类 号：TK263[动力工程及工程热物理—动力机械及工程] TH136[机械工程—机械制造及自动化]