Natural convection below a downward facing heated horizontal surface in a fluid-saturated porous medium
- Texas A and M University, College Station, TX (United States). Dept. of Mechanical Engineering
Natural convection heat transfer from a horizontal surface facing upward or downward situated in a vast fluid-saturated porous medium is one of the fundamental problems studied for better understanding of transport phenomena in geothermal energy systems. Here, the nature of natural convection under a downward facing horizontal surface in a vast fluid-saturated porous medium is numerically studied. 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 picks up toward the edges of the surface, where the heat transfer rates are consequently high. The average Nusselt number (based on the total length of the surface) is correlated as Nu = 1.142Ra{sup 0.37} in the range 30 {le} Ra {le} 1,000. The structure of the thermal and flow fields under the heated surface in a porous medium is explained.
- Sponsoring Organization:
- USDOE
- OSTI ID:
- 665298
- Journal Information:
- Numerical Heat Transfer. Part A, Applications, Journal Name: Numerical Heat Transfer. Part A, Applications Journal Issue: 3 Vol. 34; ISSN NHAAES; ISSN 1040-7782
- Country of Publication:
- United States
- Language:
- English
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