国产UP直流炉水冷壁改造方案分析

An Analysis of the Water Wall Modification Scheme for a Chinese made Once through Boiler

针对姚孟电厂300MW直流锅炉改造方案进行了水动力分析,对比了改造前后锅炉水冷壁的负流量响应特性和正流量响应特性,指出该炉垂直管圈炉膛水冷壁水动力特性不佳,低负荷运行造成水冷壁超温及管间流体和金属温差大爆管的主要原因是高质量流速设计及其产生的负流量响应特性,给类似锅炉改造提供了借鉴经验。

A hydrodynamic analysis was conducted in connection with the modification scheme of a 300 MW once-through boiler at Yaomeng Power Plant. On the basis of a comparison of the boiler water-wall negative and positive flow-rate response characteristics existing prior to and after the modification the authors noted the poor hydrodynamic characteristics of the furnace water-wall composed of vertical tube coils. An excessively high water-wall temperature and the big difference in metal and inter-tube fluid temperatures leading to tube explosion can mainly be attributed to the high mass flow speed and the resulting negative flow rate response characteristics. The above discovery may provide a helpful guide during the modification of analogous boilers.