基于量纲分析的汽轮机调节级变工况特性研究  

Research on Varying Condition Characteristic of Steam Turbine Governing Stage Based on Dimensional Analysis

作　　者：马琳[1] 胥建群[1] 曹祖庆[1] 

机构地区：[1]能源热转换及其过程测控教育部重点实验室(东南大学),江苏省南京市210096

出　　处：《中国电机工程学报》2014年第5期778-783,共6页Proceedings of the CSEE

摘　　要：基于APROS支撑平台,对喷嘴配汽方式的汽轮机调节级进行变工况热力计算,通过文献提供的实验台实验数据进行对比验证;并研究分析了部分进汽对调节级内压比的影响,确定了不同部分进汽度下调节级效率变化曲线。结果表明,部分进汽不仅造成部分进汽损失,还对调节级内压比产生影响,致使焓降与反动度发生变化,进而引起调节级效率改变。同时,以600 MW汽轮机组为例,建立了考虑部分进汽对压比影响后的调节级效率简化数学模型。在此基础之上,基于量纲分析理论,分别将全开调节阀及半开调节阀后喷嘴组压比简化表示为流量比的函数,提出一种适用于喷嘴配汽的调节级变工况热力计算方法;将计算结果与借助支撑平台的热力计算结果对比,并探讨了喷嘴调节过程中压比与反动度的变化趋势。分析表明,所提出计算方法不仅准确反映部分进汽对级内压比的影响,还对现有的调节级变工况热力计算工作做了进一步完善。Based on APROS support platform, the thermodynamic calculation of nozzle governing stage was taken, and verified through the comparison of test data which the literature offered. Moreover, the influence of partial admission on pressure ratio was analyzed, and the trend of governing stage efficiency with different partial admission degrees was also obtained. The results show that partial admission not only lead to partial admission losses, but also make an impact on pressure ratio, enthalpy and reaction degree, and finally affect the efficiency. Meanwhile, a simplified efficiency model considering the influence of partial admission on a 600 MW steam turbine was built. Then, the nozzle pressure ratio after full open valve and half one respectively, was expressed as a function of flow ratio based on dimensional analysis. this paper introduced a new method for thermodynamic calculation of nozzle governing stage. Comparing with the calculation by means of support platform, and discussing the change of pressure ratio and reaction degree, it shows that the method can reflect the influence of partial admission on pressure ratio, and further improve the accuracy of existing thermodynamic calculation.

关 键 词：调节级 部分进汽 变工况 量纲分析 压比 

分 类 号：TK263[动力工程及工程热物理—动力机械及工程]