Abstract：The temperature field performance of thermocouple calibration furnace plays an important role in the calibration of base metal thermocouple and is an important parameter to evaluate the accuracy of thermocouple calibration. In the calibration specification for base metal thermocouples, it is proposed to use thermostatic block to improve temperature field performance of thermocouple calibration furnace.In order to explore how does the thermostatic block improve the uniformity, theoretical analysis was carried out on the main heat transfer methods to achieve temperature rise in the thermocouple calibration furnace. It is holds that the main heat transfer mode in furnace is heat conduction, and the use of alloy thermostatic block with large thermal conductivity and large volume heat capacity can effectively improve the internal thermal conductivity efficiency and enhance the stability of temperature field.Furthermore, numerical simulation was used to calculate the temperature field distribution inside the furnace. The calculation results showed that compared with not placing the thermostatic block, the maximum temperature difference in the axial direction is reduced to 1/3 of the original value, and the maximum temperature difference in the radial direction is reduced to 1/2 of the original value, which is consistent with the theoretical analysis. It is shows that placing thermostatic block is an important means to optimize the temperature field of thermocouple calibration furnace.
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2024, Vol. 45 
