摘要
针对典型超(超)临界一次再热机组,在新蒸汽参数和一次再热参数不变的基础上,以5台典型超(超)临界一次再热机组为母机型,叠加1个二次再热部分,构建了二次再热机组模型;采用做功系数法及汽轮机中蒸汽等熵膨胀过程线对二次再热理想循环热效率进行理论分析及数据计算。结果表明:不同机组最佳二次再热压力为一次再热压力的19%~23%;相同机组二次再热压力与一次再热压力比值的选取范围为15%~30%;在该压力范围内,二次再热理想循环热效率比一次再热高约1%。该结论为实际工程中二次再热压力的选取提供参考。
For the typical （ultra） supercritical units with double-reheat cycle,on the basis of unchanged new steam parameters and the first reheat parameters,a double-reheat cycle is added to establish the double-re- heat unit model. The power coefficient method and the isentropic expansion process line of the steam in turbine were applied to perform theoretical analysis. Taking five typical （ultra） supercritical units as the mother units, the average heat absorption temperature and thermal efficiency of the ideal cycle and double- reheat cycle were calculated. The results show that, for different units,the best ratio of the secondary re- heat pressure to the first reheat pressure ranges from 19% to 23% ,and that for the same unit is between 15% and 30%. Within this pressure ratio selection range,the thermal efficiency of the ideal double reheat cycle is about 1% higher than that of the conventional reheat cycle. The research has certain reference sig- nificance for engineering application.
出处
《热力发电》
CAS
北大核心
2017年第1期7-10,共4页
Thermal Power Generation
关键词
二次再热机组
蒸汽参数
热效率
最佳二次再热压力
做功系数法
蒸汽等熵膨胀
double reheat unit, steam parameter, thermal efficiency, best second reheat pressure, power coef-ficient method,isentropic expansion
