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

Dates

  • Submission Date2013-05-30
  • Revision Date2014-01-28
  • Acceptance Date2014-02-24
  • Online Date2014-03-08

DOI Reference

10.2298/TSCI130530018S

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