Wärme - und Stoffübertragung

, Volume 21, Issue 5, pp 277–282 | Cite as

Measurements in a natural convection loop

  • C. Stern
  • R. Greif
Article

Abstract

Fluid temperature measurements are reported for a natural convection loop operating in the steady state regime. Averaged and fluctuating measurements were made for a toroidal thermosyphon oriented in the vertical plane that was heated over the lower half and cooled over the upper half. The measurements were made along the tube diameter at the entrance and exit of the heating sections for heat inputs from 1400 to 8410 w/m2. The amplitude of the temperature fluctuations exceeded 10 °C near the inner walls indicating the effects from recirculating flow regions at the entrances to the heating and cooling sections.

Keywords

Convection Temperature Measurement Apply Physic Heat Input State Regime 

Messungen in einem Kreislauf mit Naturumlauf

Zusammenfassung

Es wird über Messungen der Fluid-Temperatur in einem mit freier Konvektion stationär betriebenen Kreislauf berichtet. Die Messungen wurden bei leichten Fluktuationen an einem toroidalen Thermosyphon mit vertikaler beheizter Platte durchgeführt, bei dem die untere Hälfte beheizt und die obere gekühlt war. Die Temperaturenmessungen wurden über den Rohrdurchmesser am Eintritt und Austritt der beheizten Strecke für Wärmestromdichten von 1400-8410 w/m2 durchgeführt. Die Amplituden der Temperaturfluktuationen überstiegen 10 K in der Nähe der inneren Wand und zeigten dabei Rezirkulationseffekte der Strömung am Eintritt des beheizten und des gekühlten Abschnitts an.

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Copyright information

© Springer-Verlag 1987

Authors and Affiliations

  • C. Stern
    • 1
  • R. Greif
    • 2
    • 3
  1. 1.Dept. of Mechanical EngineeringVirginia Polytechnic Institute and State UniversityBlacksburgUSA
  2. 2.University of CaliforniaBerkeley
  3. 3.Dept. of Mechanical EngineeringBerkeleyUSA

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