Zusammenfassung
Das Verhalten einer Flüssigkeitsströmung in einem engen vertikalen Spalt mit einer gekühlten und einer beheizten Seitenwand wurde experimentell in einer vergangenen Studie hinsichtlich des Wärme- und Massentransports untersucht (Heiland et al. in Heat Mass Transf 43:863–870, 2007). Dieser Studie folgend wurde unter Anwendung der Flüssigkristalltechnik zur Strömungssichtbarmachung eine Untersuchung der thermischen Konvektion in einer engen Kavität unter variablem Neigungswinkel durchgeführt. Geschwindigkeits- und Temperaturfeld der Strömung wurden vermessen. Unter anderem zeigen die Ergebnisse, dass ab einem Neigungswinkel von ca. 5∘–15∘ eine drastische Änderung der Strömungs- und Temperaturfeldtopologie auftritt, welche sich qualitativ bis zu einem Neigungswinkel von 90∘ nicht mehr ändert.
Abstract
The liquid flow behaviour in a small vertical gap with a heated and a cooled sidewall was studied experimentally in a former work as far as heat and mass transfer are concerned (Heiland et al. in Heat Mass Transf 43:863–870, 2007). Following this, a study of thermal convection in a narrow cavity with variable inclination angle has been performed with a liquid crystal tracer technique for flow visualization. Velocity and temperature fields of the flow have been measured. Amongst other things the results show that from an inclination angle of approximately 5∘–15∘ on a drastic change of the velocity and temperature field topology occurs, which qualitatively will not change any more when further increasing the inclination angle up to 90∘.
Abbreviations
- a :
-
Temperaturleitfähigkeit
- b :
-
Spaltbreite
- d :
-
Tiefe
- h :
-
Höhe
- H:
-
Hue-Wert
- Pr:
-
Prandtl-Zahl
- Ra:
-
Rayleigh-Zahl
- T :
-
Temperatur
- T c :
-
Temperatur der kalten Berandung
- T h :
-
Temperatur der warmen Berandung
- ΔT :
-
Temperaturdifferenz
- v :
-
Geschwindigkeit
- x,y :
-
Kartesische Koordinaten
- β :
-
Thermischer Expansionskoeffizient
- γ :
-
Neigungswinkel
- η :
-
Dynamische Viskosität
- ρ :
-
Fluiddichte
- ν :
-
Kinematische Viskosität
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Heiland, H.G., Sommer, O. & Wozniak, G. Experimentelle Untersuchung der thermischen Konvektion in einem geneigten Spalt. Forsch Ingenieurwes 76, 87–95 (2012). https://doi.org/10.1007/s10010-012-0157-8
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DOI: https://doi.org/10.1007/s10010-012-0157-8