In the present article the question of simulation of nonstationary process of heat transport in a sensitive element of the thermoelectric transformer with an uninsulated seal is considered. The model allows defining and comparing the heating time of a thermocouple junction up to the given temperature for different types of thermocouples. In this article the values obtained by means of modelling the heat time of different thermocouples and also a temperature field in a sensitive element of the thermoelectric transformer are given.

Abstract.Researches of nonstationary processes of heating up of sensitive elements of thermocouples by means of one-dimensional and two-dimensional mathematical models of heat transfer are conducted. By the created models are defined duration of heating up of the sensitive elements necessary for achievement of the temperature of the thermocouple within a permissible deviation from rated direct current characteristic for three types of thermocouples -K, L and S. Distinctions in the results received by means of onedimensional and two-dimensional models of heat transfer are shown and justified. For surface thermo-electric transformers, temperature measurement conditions are simulated in case of different value of air gap between the heater and thermocouple surface. It is shown that the value of a gap has an essential impact on minimum necessary time of measurement. Change of duration of heating up of thermocouple from heatphysical characteristics of the typical materials which are used in the case of manufacture of sensing elements is probed.

One-dimensional and two-dimensional models of heat transfer are given in operation for research of the main characteristics of process of temperature measurement by means of surface thermocouples. Results of numerical evaluations of the relative error of the measurement arising owing to existence of air gap between a sensitive element of the thermocouple and object of measurement are provided. It is revealed that the measurement error in case of observance of necessary time of heating up (set minimum required time of measurement) can be lowered to level of an allowed error.

Abstract. Numerical research of integral characteristics of process of heattransfer in sensitive elements of R, A and B types thermocouples in case of measurement of high temperatures (more than 900 K) is executed. Theoretical dependences of minimum necessary duration of heating up of the thermocouple on value of temperature on boundary of a sensitive element are received. It is shown the thermocouple of R type requires bigger time of heating for obtaining satisfactory accuracy of measurements. Temperature fields in sensitive elements of the specified thermocouples are received. It is shown that distribution of temperature on the thermocouple not linearly and has similar character for the researched thermocouples.

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