- Tytuł:
- Reduction of dynamic error in measurements of transient fluid temperature
- Autorzy:
- Jaremkiewicz, M.
- Powiązania:
- https://bibliotekanauki.pl/articles/240052.pdf
- Data publikacji:
- 2011
- Wydawca:
- Polska Akademia Nauk. Czytelnia Czasopism PAN
- Tematy:
-
analiza niepewności
model pierwszego obiektu
pomiar temperatury
stała czasowa
warunki przejściowe
first-order model
temperature measurement
time constant
transient conditions
uncertainty analysis - Opis:
- Under steady-state conditions when fluid temperature is constant, temperature measurement can be accomplished with high degree of accuracy owing to the absence of damping and time lag. However, when fluid temperature varies rapidly, for example, during start-up, appreciable differences occur between the actual and measured fluid temperature. These differences occur because it takes time for heat to transfer through the heavy thermometer pocket to the thermocouple. In this paper, a method for determinig transient fluid temperature based on the first-order thermometer model is presented. Fluid temperature is determined using a thermometer, which is suddenly immersed into boiling water. Next, the time constant is defined as a function of fluid velocity for four sheated thermocouples with different diameters. To demonstrate the applicability of the presented method to actual data where air velocity varies, the temperature of air is estimated based on measurements carried out by three thermocouples with different outer diameters. Lastly, the time constant is presented as a function of fluid velocity and outer diameter of thermocouple.
- Źródło:
-
Archives of Thermodynamics; 2011, 32, 4; 55-66
1231-0956
2083-6023 - Pojawia się w:
- Archives of Thermodynamics
- Dostawca treści:
- Biblioteka Nauki