火力发电厂加热器端差应达值的确定

The Determination of Target Value of Heater Temperature Difference of Coal-fired Power Plant

通过对火电厂加热器的结构组成及换热过程的分析,提出了计算加热器端差数学方法并建立数学模型。利用N600-16.67/537/537机组100%、75%和50%THA设计工况及75%、50%THA试验工况的相关参数,根据所提供的计算方法,对加热器的应达值进行了计算。结果表明,由该方法计算所得到的值,在3种设计工况下,与设计端差基本相符;与两试验工况下的端差值也基本相符;加热器设计端差与其端差应达值并不是同一个值,端差应达值随加热器工况变化而变;端差应达值对故障加热器能够进行判别,也是加热器换热性价是否最佳的判据。

On the basis of the analysis about structures of heaters and the processes of heat transfer in coal-fired power plant,a computing mathematical method about the temperature difference of heater was put forward and a mathematical model was established in this paper. Using relevant parameters of N600-16.67/537/537 unit in 100% ,75% ,50% THA design work conditions and 75% ,50% THA test work conditions, according to the computing method provided in this paper,the temperature difference should be target value were calculated. Results showed that the values obtained by the computing method were basically consistent with the designed temperature differences in the three design work conditions, as well as the two test work conditions. The design temperature difference was different from the grant value. The target value changed with the work conditions of heater, used to distinguish the fault heater, and also could be a criterion to judge whether the heater in its best heat transfer work condition.