接触长度对镍铬-金铁热电偶测温精度影响的研究

A research on effect of contact length on measuring accuracy of nickel-chromium/gold-iron thermocouple

为了提高热电偶在低温下的测量精度,基于傅里叶导热定律建立了测温误差的分析模型,分析了影响测温精度的主要因素,对热电偶与被测对象不同接触情况下镍铬-金铁热电偶的热电势进行了测量和研究。研究结果表明:温度越低,测量误差越大;增加接触长度,可减小误差。

In order to improve the accuracy of thermocouple measurement at low temperatures, the measurement error analysis model was established based on the Fourier law of heat conduction, the main factors to affect the temperature accuracy of the thermocouple measurement was analyzed, the electric potential value of the nickel-chromium/gold-iron thermoeouple with different contact situations was measured and studied at different temperature. The results show that the lower the temperature bigger the erroris. And the erroer can be reduced by increasing the contact length.