Open AccessNatural Convection Cooling of a Heat Source Placed at the Bottom of a Square Cavity. Effect of Source Length, Position, Thermal Condition and Prandtl Number
Author(s) -
Horimek Abderrahmane,
El-Amria Nekag
Publication year - 2020
Publication title -
heat and technology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.283
H-Index - 29
ISSN - 0392-8764
DOI - 10.18280/ijht.380317
Subject(s) - prandtl number , nusselt number , natural convection , rayleigh number , mechanics , thermodynamics , heat transfer , convection , thermal , physics , materials science , reynolds number , turbulence
Cooling process of a heat source placed at the bottom side of a cold-walled cavity (TC) by means of natural convection has been studied numerically in this work. Two thermal conditions have been assumed at the source (q-imposed or T-imposed). The effects of Rayleigh number (Ra=10+3→10+6), source length (SL=0.1→1.0), source position (D) compared to left side, in addition to the effect of the number of Prandtl (Pr=0.71→10+2) were analyzed with ample details. For a source at the center of the bottom side, results showed an increase of flow and temperature disturbance with increasing Ra and/or SL, with an enhancement of both local and mean Nusselt numbers. Particular exceptions were noticed for high Ra values for the second heating type. For all considerations, the case of SL=0.1 makes an exception where a very good heat exchange rate is recorded. When the source is no longer centered, Clearer difference between this case and the previous one was recorded, especially for small D values. Very good heat exchange rate is recorded for D=0.0 for all considerations, with remarkable amount of difference compared the closest one to it, followed by a progressive decrease until the case of source at the center. Finally, Prandtl number (Pr) effect analysis showed an increase of the heat transfer rate with a clear amount from Pr=0.71 until Pr=5.0, followed by a slight increase for higher Pr values until stabilization for Pr>50.0. The good exploitation of the intervening parameters’ parameters, allows ensuring the best cooling of the source.