摘要
汽轮发电机组参与调峰运行,汽缸的膨胀是影响机组机动性及运行安全性的重要因素之一。由二维圆筒壁非稳态导热微分方程,推导得到内部蒸汽沿轴向线性分布、随时间非线性变化、外壁绝热的圆筒壁温度场解析解。通过与有限元计算结果进行对比,表明所得模型计算精度高、速度快。针对不同结构的汽缸,经过一些合理假设,将汽缸复杂的结构分解成简单的子结构,得到了汽缸轴向膨胀的计算模型。该模型还可以用于汽缸轴向膨胀的实时监测,所采用的推导方法和得到的膨胀计算公式亦可用于其它具有类似边界条件的厚壁圆筒部件的相关分析。
In the event of turbo - generator set participating into the peak - regulating operation, the thermal expansion of turbine casing is one of the most important factors affecting flexibility and safety of the steam turbine. Starting from unstable differential equation of heat conduction for a two - dimentional （2 - D） cylindrical wall, in which the internal steam is linearly distributing along the axial direction, and varying along with the time, and external wall is adiabatic, has been obtained from deduction, and a comparison with the result from finite- element calculation being carried out. It shows that the obtained model has high precison and rapid calculation. Directing against steam cylinders with different structure, and through some reasonable assumptions, a complicated cylinder structure can be decomposed into simple sub - structures, and a cylinder model of axial expansion has been obtained. The said model can also be used for real - time monitoring of axial expansion for the steam cylinder. The deducing method applied and the expansion calculating formula obtained can also used for other correlative analysis of cylindrical components with thick wall having similar boundary conditions.
出处
《热力发电》
CAS
北大核心
2007年第7期8-12,共5页
Thermal Power Generation
关键词
汽缸
子结构
二维轴对称体
导热微分方程
热膨胀
steam turbine
cylinder
sub-structure
2- D axi-symmetric solid
differential equation of heat conduction
thermal expansion
