Method for determining thermal conductivity and thermal capacity per unit volume of earth in situ
Abstract
A method for determining the thermal conductivity of the earth in situ is based upon a cylindrical probe (10) having a thermopile (16) for measuring the temperature gradient between sets of thermocouple junctions (18 and 20) of the probe after it has been positioned in a borehole and has reached thermal equilibrium with its surroundings, and having means (14) for heating one set of thermocouple junctions (20) of the probe at a constant rate while the temperature gradient of the probe is recorded as a rise in temperature over several hours (more than about 3 hours). A fluid annulus thermally couples the probe to the surrounding earth. The recorded temperature curves are related to the earth's thermal conductivity, k.sub..infin., and to the thermal capacity per unit volume, (.gamma.c.sub.p).sub..infin., by comparison with calculated curves using estimates of k.sub..infin. and (.gamma.c.sub.p).sub..infin. in an equation which relates these parameters to a rise in the earth's temperature for a known and constant heating rate.
- Inventors:
-
- LaJolla, CA
- Issue Date:
- OSTI Identifier:
- 864286
- Patent Number(s):
- 4343181
- Assignee:
- United Stated of America as represented by United States (Washington, DC)
- DOE Contract Number:
- E(04-3)-1318
- Resource Type:
- Patent
- Country of Publication:
- United States
- Language:
- English
- Subject:
- method; determining; thermal; conductivity; capacity; unit; volume; earth; situ; based; cylindrical; probe; 10; thermopile; 16; measuring; temperature; gradient; sets; thermocouple; junctions; 18; 20; positioned; borehole; reached; equilibrium; surroundings; means; 14; heating; set; constant; rate; recorded; rise; hours; fluid; annulus; thermally; couples; surrounding; curves; related; infin; gamma; comparison; calculated; estimates; equation; relates; parameters; heating rate; surrounding earth; temperature gradient; thermal conductivity; unit volume; thermocouple junctions; thermal equilibrium; constant rate; thermocouple junction; /73/374/
Citation Formats
Poppendiek, Heinz F. Method for determining thermal conductivity and thermal capacity per unit volume of earth in situ. United States: N. p., 1982.
Web.
Poppendiek, Heinz F. Method for determining thermal conductivity and thermal capacity per unit volume of earth in situ. United States.
Poppendiek, Heinz F. Fri .
"Method for determining thermal conductivity and thermal capacity per unit volume of earth in situ". United States. https://www.osti.gov/servlets/purl/864286.
@article{osti_864286,
title = {Method for determining thermal conductivity and thermal capacity per unit volume of earth in situ},
author = {Poppendiek, Heinz F},
abstractNote = {A method for determining the thermal conductivity of the earth in situ is based upon a cylindrical probe (10) having a thermopile (16) for measuring the temperature gradient between sets of thermocouple junctions (18 and 20) of the probe after it has been positioned in a borehole and has reached thermal equilibrium with its surroundings, and having means (14) for heating one set of thermocouple junctions (20) of the probe at a constant rate while the temperature gradient of the probe is recorded as a rise in temperature over several hours (more than about 3 hours). A fluid annulus thermally couples the probe to the surrounding earth. The recorded temperature curves are related to the earth's thermal conductivity, k.sub..infin., and to the thermal capacity per unit volume, (.gamma.c.sub.p).sub..infin., by comparison with calculated curves using estimates of k.sub..infin. and (.gamma.c.sub.p).sub..infin. in an equation which relates these parameters to a rise in the earth's temperature for a known and constant heating rate.},
doi = {},
journal = {},
number = ,
volume = ,
place = {United States},
year = {1982},
month = {1}
}