Natural convection heat transfer in a saturated porous matrix whose permeability is anisotropic is analyzed by a finite-element method. A specific problem involves the convection in a square box heated from below. The Rayleigh number is defined at vertical permeability, according to Kvernvold and Tyvand. The calculated critical Rayleigh numbers agree well with the linear stability theory. Variations of the Nusselt numbers with the Rayleigh numbers for various values of the x-to-y permeability ratio and cell number are calculated. It is found that the ratio and cell numbers have a great effect on the properties of natural convection heat transfer and the number of convection cells realized in a square space. Unsteady temperature distribution and Nusselt number changes in the transient state are also calculated.
|Number of pages||6|
|Journal||Nippon Kikai Gakkai Ronbunshu, B Hen/Transactions of the Japan Society of Mechanical Engineers, Part B|
|Publication status||Published - 1991 Dec|
ASJC Scopus subject areas
- Mechanical Engineering