Natural convection below a downward facing heated horizontal surface in a fluid saturated porous medium
- Texas A and M Univ., College Station, TX (United States). Dept. of Mechanical Engineering
The nature of natural convection under a downward facing heated horizontal surface in a vast fluid-saturated porous medium is studied numerically. This is one of the fundamental problems which must be addressed in order to obtain a complete understanding of the transport phenomena in geothermal energy systems. The two-dimensional flow is considered to be symmetric about the mid-vertical plane under the surface, and numerical calculations are presented for one-half of the domain. The flow and thermal fields demonstrate no boundary layer behavior, and hence similarity and integral analyses are not possible. A layer of thermally stratified fluid grows under the central region of the surface, which inhibits flow. Convection increases towards the edges of the surface where the heat transfer rates are consequently higher. The average Nusselt number (based on the total length of the surface) is correlated as Nu = 1.142 Ra{sup 0.37} in the range 30 {le} Ra {le} 1,000. The structure of thermal and flow fields under the heated surface in a porous medium is explained.
- OSTI ID:
- 485086
- Report Number(s):
- CONF-970146--; ISBN 1-890277-03-7
- Country of Publication:
- United States
- Language:
- English
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