300MW发电机组凝汽器内空化现象的研究

Research on cavitation phenomenon in condenser for 300MW units

以汉川电厂凝汽器为研究对象,对空化现象的形成和发展过程进行分析,指出气态微核膨胀和汽化这两个子过程在空化形成中的地位以及二者间的联系.从温度控制和压力控制这两个方面分析了影响凝汽器内空化形成与发展的各种因素,并提出相应的抑制空化现象发生的方法.最后,给出通过改变虹吸井堰顶高程来抑制空化这一措施的计算方法和结果.提出的分析和措施对解决类似的空化问题有一定的参考作用.

Taking the condenser for 300MW units in Hanchuan Thermal Power Plant as an object of study, the development of cavitation phenomenon in the condenser is analyzed. During the development, the expansion of gaseous microkernels and the boil off of water are the two basic processes and they have different effects on cavitation formation. Factors that affect the development of cavitation in the condenser are analyzed from the aspects of temperature control and pressure control. Based on the above analysis, a mathematical method for calculating vacuum value is proposed. At last, improvement measures for abating cavitation by changing elevation of siphon-well checkgate are presented.