摘要
准确的换热系数计算公式是数值分析汽轮机高压缸温度分布、应力及汽密性的基础。目前国内外关于核电汽轮机高压缸换热系数的研究较少,汽缸表面换热系数一直没有统一的公式。本文选用并修正了高压缸内表面换热系数计算公式,对比高压缸壁面温度的计算值和实际监测数据,得到了适用于核电汽轮高压缸的换热系数模型,求解了汽缸温度分布,并对高压缸的应力及中分面汽密性进行了分析。结果表明:该模型具有较高的计算精度,最大误差为4.3%;停机过程中高压缸各表面换热以强迫对流为主,高压缸进汽及排汽处缸表面的换热系数量级在1 000~2 000 W/(m^2·K);停机过程中高压缸内外壁最大温差为29.9℃。
The precise calculation formula of heat transfer coefficient is the basis for numerical analysis of the temperature distribution,stress,and vapor tightness of high pressure cylinder for turbine.At present,there are few researches on the heat transfer coefficient of high pressure cylinder for nuclear power turbine at home and abroad,and there are no general formulas for the surface heat transfer coefficient of the cylinder.This study selects and corrects the calculation formula of the internal surface heat transfer coefficient of the high pressure cylinder.By contrasting the calculated data of the wall temperature of the high pressure cylinder with the actual measured data,a heat transfer coefficient model suitable for the high pressure cylinder of the nuclear power turbine is obtained.Besides,the temperature distribution,stress and the middle facet vapor tightness of high pressure cylinder for turbine are analyzed.The results show that this model has a high calculation accuracy with a maximum error of 4.3%.During the shutdown process,the surface heat transfer of the high pressure cylinder is mainly forced convection.The surface heat transfer coefficient at the inlet and exhaust of the high pressure cylinder is in the range of 1 000~2 000 W/(m2·K).The maximum temperature difference between the internal and external walls of the high pressure cylinder during the shutdown process is 29.9℃.
作者
魏红明
谢诞梅
曹超
李浩
WEI Hongming;XIE Danmei;CAO Chao;LI Hao(Northwest Branch,China Datang Corporation Science and Technology Research Institute Co.,Ltd.,Xi’an 710065,China;School of Power and Mechanical Engineering,Wuhan University,Wuhan 430072,China)
出处
《热力发电》
CAS
北大核心
2018年第9期109-114,共6页
Thermal Power Generation
关键词
核电
汽轮机
高压缸
汽密性
换热系数
计算公式
温度场
数值模拟
nuclear power
turbine
high pressure cylinder
vapor tightness
heat transfer coefficient
computational formula
temperature field
numerical simulation
