Fluid temperature measurement under transient conditions

• Autorzy: Taler J. , Jaremkiewicz M. , Taler D. , Sobota T.
• Języki publikacji: EN

Abstrakty

EN

Under steady-state conditions when fluid temperature is constant, there is no damping and time lag and temperature measurement can be accomplished with high degree of accuracy. However, when fluid temperature is varying rapidly as during start-up, quite appreciable differences occur between the actual fluid temperature and the measured temperature. This is due to the time required for the transfer of heat to the thermocouple placed inside a heavy thermometer pocket. In this paper, two different techniques for determining transient fluid temperature based on the first and second order thermometer model are presented. The fluid temperature was determined using the temperature indicated by the thermometer, which was suddenly immersed into boiling water. To demonstrate the applicability of the presented method to actual data, the time constant of the sheathed thermocouple placed in the air stream was estimated as a function of the air velocity.

Słowa kluczowe

EN

first and second order models; temperature measurement; time constant; transient conditions; uncertainty analysis

PL

analiza niepewności; model pierwszego i drugiego rzędu; pomiar temperatury; stała czasowa; warunki nieustalone

• Wydawca: Wydawnictwo Instytutu Maszyn Przepływowych PAN ; Komitet Termodynamiki i Spalania PAN
• Czasopismo: Archives of Thermodynamics
• Rocznik: 2009
• Tom: Vol. 30, no. 3
• Strony: 75--88
• Opis fizyczny: Bibliogr. 17 poz.,Fot., rys., wykr., wz.

Twórcy

autor

Taler J.

autor

Jaremkiewicz M.

autor

Taler D.

autor

Sobota T.

• Cracow University of Technology, Division of Power Engineering, Al. Jana Pawia II 37, PL-31-864 Kraków, Poland,

Bibliografia

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