铅塔燃烧室烟气温度测试伪信号输出研究

根据燃烧室内烟气静态和动态的不同情况，对热电偶以及隔热罩的辐射热损失进行了推导与计算，结果显示：静态情况下抽气热电偶测试伪信号输出造成铅塔燃烧室内烟气温度有伪波动的现象发生，而动态情况下伪信号输出可能掩盖铅塔燃烧室烟气温度波动现象，造成烟气温度处于伪静态的现象，这不仅不能真实地反映烟气温度分布情况，而且会给铅塔燃烧室燃烧工况及烟气温度诊断带来假象。当隔热罩与热电偶黑度值增加到一定程度而保持不变时，由黑度变化而引起测试伪信号输出量及其变化量达到最大值，必须对输出信号进行修正。此研究结果有利于铅塔燃烧室烟气真实温度的在线检测。

STUDY ON SMOKE TEMPERATURE FALSE MEASUREMENT SIGNALS EXPORTED BY THE THERMOCOUPLE IN COMBUSTION CHAMBER OF LEAD COLUMN

Based on increasing missives of the thermocouple and heat insulation,the losses of radiant heat of the thermocouple and the heat insulation were deduced and calculated according to static and dynamic state of smoke in the combustion chamber.The result reveals that false measurement signals exported by the thermocouple with air pump in static state would cause false wave of smoke temperature,and that false measurement signals exported by the thermocouple with air pump in dynamic state concealed real wave of smoke temperature in the combustion chamber of lead column,and would lead to false static state of smoke temperature,which wouldn't truly reflect distributive case of smoke temperature and would cause some feints to burning case and diagnosis of smoke temperature in the combustion chamber of lead column.When emissivity values of the thermocouple and heat insulation increasingly got to and hold their maximum,False measurement signals and their changes exported by the thermocouple with air pump due to variational emissivity values got to maximum.Therefore,the false measurement signals muse be corrected.These research will more benefited to on-line control of actual temperature in combustion chamber.