摘要
随着汽轮机叶片进口参数越来越高,叶片对材料的高温力学性能提出了更高的要求,在高温下材料的力学特性远低于其在常温下的所承受的范围,在高温下材料会发生蠕变和应力松驰现象,应用"characteristic strain"蠕变模型来分析高温叶片的蠕变和应力松弛行为,该蠕变模型是阿尔斯通叶片专家J.Bolton将诺顿蠕变模型优化后得到的,该蠕变模型相比于诺顿蠕变模型大大提高了计算效率。本次高温叶片有限元蠕变计算,评估了叶片在高温下的安全性及机械设计完整性,良好地指导了叶片结构设计,且得到了高效、精确的高温蠕变计算方法。
With increasingly higher inlet parameters of steam turbine, blades are faced with stricter requests for high temperature characteristics. In case of high temperature, mechanics characteristics of materials are rather different from normal temperature condition. The allowable range will become smaller, and some phenomenons will appear, such as creep and stress relaxation. ＂Characteristic strain＂ creep model is carried out to analyse phenomenons of creep and stress relaxation for blades. This model was proposed by J. Bohon, a steam tubine blade expert from Alstom, and this model was based on Norton＇s creep model. FEA calculations for high temperature blades are carried out to evaluate security and mechanical design integrity, which is of great inportance to ensure security of blades and guide structural design. And an method is obtained, which is effiective for calculating high temperature creep.
出处
《汽轮机技术》
北大核心
2017年第5期326-328,共3页
Turbine Technology
