正平衡法在电站锅炉空气预热器热效率计算中的应用  

Application of Direct Balance Method in Thermal Efficiency Calculation of Air Pre-heater of Boiler in Thermal Power Plant

作　　者：吴尔夫 卓旭升[1] 陈节涛 王为 WU Erfu;ZHUO Xusheng;CHEN Jietao;WANG Wei(School of Electrical and Information Engineering,Wuhan Institute of Technology,Wuhan 430205,China;GUO DIAN Hanchuan Power Plant Co.LTD,Hanchuan 431614,China)

机构地区：[1]武汉工程大学电气信息学院,湖北武汉430205 [2]国电汉川发电有限公司,湖北汉川431614

出　　处：《武汉工程大学学报》2018年第5期580-584,共5页Journal of Wuhan Institute of Technology

基　　金：湖北省教育厅科学技术研究项目(NO.B2015317)

摘　　要：根据正平衡法的原理,针对燃煤锅炉的空气预热器提出一种能够实时计算其热效率的简易方法,其算法原理是:利用空预器入口和出口处烟温的差值和烟气流量计算出烟气经过空预器释放的热量,以及利用空气经过空预器后的升温空气流量计算出其吸收的热量,从而得到空预器的热效率值。由于烟气的实际流量未知,本文利用燃烧反应式计算出燃料燃烧后生成的干烟气和水蒸气的流量,再加上过剩的空气量,最终得到了烟气的计算流量。将该算法用MATLAB语言实现编程后,可对空预器的热效率进行实时计算并绘出运行曲线,这将有助于机组运行人员监视空预器的运行状况。According to the principle of direct balance method,this paper presents an algorithm for computing the thermal efficiency of air pre-heater of coal-fired boiler in real time operation. First,the released heat from flue-gas was calculated by using its temperature difference between the inlet and outlet of the pre-heater and itsvolume flow rate. Then,the absorpted heat was calculated by the volume flow rate of the air flowing through thepre-heater with temperature increment. Finally,the heat efficiency of the air pre-heater was obtained by theratio of the above two heat flow rates. Because the real flue-gas＇ s volume flow rate was unknown,this papersolved this problem via calculating the volume flow rates of dry flue-gas and water vapor produced by chemicalreaction of coal combustion,and adding the surplus air volume flow rate. After programmed with MATLABlanguage,this algorithm can calculate the real-time thermal efficiency of the air pre-heater and draw its curve,which is expected to help the technicians to monitor the operation of the air pre-heater.

关 键 词：空气预热器 传热热效率 烟气流量计算 正平衡法 

分 类 号：TK222[动力工程及工程热物理—动力机械及工程]