物体热发射率在线测试仪

摘要

为了满足航空工业发射率在线测量的迫切需求,提出了一种单罩比值的发射率测量方法.通过热网络法推导了测量原理,对半球罩探测器在测量过程遇到的热电堆冷端温度变化和半球罩背景辐射进行了补偿,得到被测表面实际的辐射信号,再通过若干标准样板对信号电压的比值进行标定得到发射率.实测结果表明,本方法测量发射率的误差低于±0.05,符合在线测量的要求.%In order to meet the urgent needs of emissivity online measurement in the aviation industry,a method is proposed to measure the emissivity of the single hemisphere cover ratio.The measurement principle is derived from the heat net method.In the measurement for hemisphere cover detector,the temperature variation of the thermopile' s cold junction and the ambient infrared radiation from the hemisphere cover are compensated,the real radiation signal of the measured surface is gotten.Then,the emissivity is obtained by calibrating the ratio of signal voltage by using several standard plates.The experimental results show that the measurement error is less than ± 0.05,and this method satisfies the requirements of online measurement.