Kompetentnost' 7/138/2016

ISSN 1993-8780

RESEARCH 33

Thermocouple Contact’s Influence

with the Measurement Object on the Duration

of the Temperature Recording

Yu.K. Atroshenko, Senior Lecturer, National Research Tomsk Polytechnic University (Power Engineering Institute), Department of Automation of Heat Power Processes, Tomsk, Russia, julie55@tpu.ru

Dr. E.V. Kravchenko, Assistant Professor, Tomsk Branch, FSAEI FVT, ASMS, National Research Tomsk Polytechnic

University (Power Engineering Institute), Department of Automation of Heat Power Processes, Tomsk, Russia, kevatp@tpu.ru

key words

surface thermocouple, thermocouple, heat transfer, isolated and uninsulated

seal, simulation, temperature measurement error

References

The heat transfer model is developed for a sensitive element of the thermoelectric transformer with an isolated cell. The results of numerical modeling of the heat transfer process in case of heating up the surface of thermoelectric transformer are given. The required characteristic times of heating up thermocouples for support of satisfactory errors of measurements are defined. It is shown that heating up duration for thermocouples with an isolated seal slightly exceeds heating up duration for thermocouples with an uninsulated seal. The set dependencies of duration of heating up on the size of the air gap between the thermocouple and a surface of the measurement object we are also given.

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