THERMAL SCIENCE

International Scientific Journal

NATURAL CONVECTION AIR FLOW IN VERTICAL UPRIGHT-ANGLED TRIANGULAR CAVITIES UNDER REALISTIC THERMAL BOUNDARY CONDITIONS

ABSTRACT
This paper presents an analytical and numerical computation of laminar natural convection in a collection of vertical upright-angled triangular cavities filled with air. The vertical wall is heated with a uniform heat flux; the inclined wall is cooled with a uniform temperature; while the upper horizontal wall is assumed thermally insulated. The defining aperture angle φ is located at the lower vertex between the vertical and inclined walls. The finite element method is implemented to perform the computational analysis of the conservation equations for three aperture angles φ (= 15º, 30º and 45º) and height-based modified Rayleigh numbers ranging from a low Ra = 0 (pure conduction) to a high 109. Numerical results are reported for the velocity and temperature fields as well as the Nusselt numbers at the heated vertical wall. The numerical computations are also focused on the determination of the value of the maximum or critical temperature along the hot vertical wall and its dependence with the modified Rayleigh number and the aperture angle.
KEYWORDS
PAPER SUBMITTED: 2013-05-30
PAPER REVISED: 2014-01-28
PAPER ACCEPTED: 2014-02-24
PUBLISHED ONLINE: 2014-03-08
DOI REFERENCE: https://doi.org/10.2298/TSCI130530018S
CITATION EXPORT: view in browser or download as text file
THERMAL SCIENCE YEAR 2016, VOLUME 20, ISSUE Issue 5, PAGES [1407 - 1420]
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