300MW汽轮机内异质均质凝结的实验研究  

Experimental Study of Heterogeneous and Homogeneous Condensation in a 300 MW Turbine

作　　者：牛凤仙[1] 蔡小舒[1] 宋延勇[1] 宁廷保[1] 吴广臣[1] 徐则林 岑岺山 郭养富 张瑾 李岗 

机构地区：[1]上海理工大学动力工程学院,上海市杨浦区200093 [2]国电科环节能中心,北京市海淀区100070 [3]漳山发电有限公司,山西省长治市046021

出　　处：《中国电机工程学报》2009年第29期1-6,共6页Proceedings of the CSEE

基　　金：国家自然科学基金重点项目(50336050);上海市研究生创新基金项目(JWCXSL0902)~~

摘　　要：为减少湿蒸汽损失,汽轮机低压缸设计中需要知道湿蒸汽的水滴参数。水滴参数与凝结过程紧密相连,但目前已有的凝结理论模型和实验室中的喷嘴实验结果不能直接应用于真实的汽轮机中。简单介绍了汽轮机低压缸内湿蒸汽的凝结机制和新研制的改进型湿蒸汽测量系统的工作原理。基于实测变背压过程中直接空冷机组低压汽轮机末级后的蒸汽湿度参数并结合凝结机制,分析变背压过程中蒸汽湿度参数的变化规律及原因,证实了汽轮机中存在异质凝结现象以及凝结从异质为主向均质为主转变的过程。Steam turbine low pressure （LP） cylinder design aims at reducing the wetness loss. It requires knowledge of steam droplet diameter distribution in the flow tunnel, which tightly relates to the condensation process. However, currently available models of condensation theory and the experiment results obtained from the steam nozzle can not be directly applied to assessment of the real steam turbine condensation. This paper briefly introduced the nucleation mechanism of wet steam in LP cylinders of steam turbines and the working principle of the newly developed wet steam measuring instrument. The correlation of steam wetness parameters with the back pressure was analyzed based on actual measurement of steam wetness parameters behind the last stage of the direct-cooling LP unit and the condensation mechanism. The existence of heterogeneous condensation and the transition of dominating condensation from heterogeneous to homogeneous over the back-pressure change were demonstrated by the actual measurement results.

关 键 词：汽轮机 湿蒸汽 异质凝结 均质凝结 测量 

分 类 号：TM261[一般工业技术—材料科学与工程]