摘要
为了研究在高温下某660MW超超临界汽轮机高压转子的蠕变强度,利用有限元计算方法分析了转子在额定工况下的温度和应力分布,并采用幂率模型和孔洞长大机理预测了该转子在2×10^5h工作中的蠕变行为.研究结果表明：在额定工况下,转子最高内应力低于屈服极限,处于纯弹性变形状态;转子内大部分区域温度在300～600℃,已进入蠕变温度范围.蠕变与热弹性耦合分析表明：蠕变会引起转子内部应力的重新分布,转子前轴封圆弧段的蠕变应变较高,而且多轴应力对该区域蠕变韧度的影响明显,应当引起足够重视.
Finite Element Method was used for analyzing the temperature and stress distributions of the rotor under rated condition, in order to study creep strength of a 660MW ultra super-critical steam-turbine high-pressure rotor under high temperature. The rotor＇s creep behavior during operation of 200 000 hours was numerically predicted based on power-law model and void-growth mechanism. Results indicate that the highest inner stress of the rotor is lower than the yield limit under rated condition, being the status of simple elastic deformation. The temperature inside the most area of the rotor is between 300 - 600℃, indicating it raised into the temperature range of creep. Analysis of creep and thermo-elastic coupling indicate that, creep would cause the inner stress of the rotor to redistribute. The higher creep deformation occurs at an arc zone around the front-seal. Furthermore, the multi-axial stress would influence the creep ductility obviously within this area. It should be deserved extra attention.
出处
《动力工程》
CSCD
北大核心
2009年第2期99-103,共5页
Power Engineering
关键词
超超临界汽轮机
高压转子
高温蠕变
强度
寿命预测
ultra-supercritical steam turbine
high-pressure rotor
high-temperature creep
strength
life prediction
