Abo Bibliothek: Guest

ISSN Online: 2377-424X

ISBN Print: 0-85295-345-3

International Heat Transfer Conference 10
August, 14-18, 1994, Brighton, UK

NUMERICAL SIMULATION OF THREE-DIMENSIONAL FREE CONVECTION IN A HORIZONTAL POROUS ANNULUS

Get access (open in a dialog) DOI: 10.1615/IHTC10.3840
pages 319-324

Abstrakt

A numerical study of free convection three-dimensional (3D) flows in a saturated porous layer bounded by two horizontal and isothermal cylinders is reported. The numerical algorithm integrates the Darcy-Boussinesq's equations formulated in terms of pressure and temperature. The dependent variables (P,T ) are expressed using truncated spectral representations with Chebyshev polynomials in radial direction and Fourier series in both axial and azimuthal periodic directions. Then the collocation -Chebyshev method with a diagonalization procedure is considered to compute the pressure and temperature fields.
The structures of the 3D flows which appear in the vicinity of the transition between the 2D unicellular flow and the three-dimensional one are particularly investigated for differents values of the radius ratio of the two cylinders (R ) and the longitudinal aspect ratio (H ). For R = 2, H = 2 and R = 21/2, H = 2, the critical Rayleigh number of this transition is determined numerically. The results are compared with experimental measurements obtained in previous works.