Thermal conductivity of frozen soils

Thermal conductivity measurements of two frozen soils, Leda clay and Sudbury silty clay, taken at temperatures between 0 and −22 °C by means of a thermal probe and a transient heat flow technique, compare favorably with estimates of thermal conductivity calculated by the DeVries method. Both measured and estimated values show a similar trend of increasing thermal conductivity as the temperature is lowered and the ice content grows. This increase is associated with the higher thermal conductivity of ice compared with that of water.

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Exploring ice content on partially saturated frozen soils using dielectric permittivity and bulk electrical conductivity measurements

E3S Web of Conferences ◽

10.1051/e3sconf/20160907005 ◽

2016 ◽

Vol 9 ◽

pp. 07005 ◽

Cited By ~ 1

Author(s):

Yanxin Mao ◽

Enrique Romero ◽

Antonio Gens

Keyword(s):

Electrical Conductivity ◽

Dielectric Permittivity ◽

Conductivity Measurements ◽

Frozen Soils ◽

Partially Saturated ◽

Bulk Electrical Conductivity ◽

Ice Content

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Soil thermal conductivity dataset

10.5194/ismc2021-84 ◽

2021 ◽

Author(s):

Hailong He

Keyword(s):

Thermal Conductivity ◽

Land Surface ◽

Pulse Method ◽

Time Domain Reflectometry ◽

Soil Thermal Conductivity ◽

Thermal Probe ◽

Line Heat Source ◽

Steady State Method ◽

Needle Probe ◽

Transient Heat Flow

<p>Soil thermal conductivity (STC) is required parameter for coupled water and heat transport for land surface models. However, unlike soil hydraulic properties, no global dataset is available for STC. The objective of this study was to collate literature data and to take new measurements in order to establish a big STC dataset that would facilitate the evaluation and development of STC models. We collected over 8000 STC measurements made on over 400 soil types around the world following rigid filtering criteria and processes. All the STC data in the dataset were based on transient-heat-flow methods (e.g., non-steady-state method, line-heat source, needle probe, thermal probe, dual and single probe heat pulse method, thermo-time domain reflectometry). Each soil contains at least five water contents in addition to known soil physical properties such as texture and bulk density. This presentation will give a brief introduction about the STC dataset as well as call for contributions to it.</p>

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Downhole Measurements of Thermal Conductivity in Geothermal Reservoirs

Journal of Pressure Vessel Technology ◽

10.1115/1.3454580 ◽

1977 ◽

Vol 99 (4) ◽

pp. 607-611 ◽

Cited By ~ 9

Author(s):

H. D. Murphy ◽

R. G. Lawton

Keyword(s):

Thermal Conductivity ◽

Exact Solution ◽

Heat Flow ◽

Thermal Contact ◽

Approximate Solutions ◽

Laboratory Measurements ◽

Transient Effect ◽

Transient Heat Flow ◽

Geothermal Wells ◽

Downhole Measurements

The line source method of determining thermal conductivity is extended to include the transient effect associated with the fluid in flowing geothermal wells. The general equations describing transient heat flow are utilized. Approximate solutions are derived and compared to the exact solution of the general equations. The proposed method is operationally simple since the heater, and the associated problems of obtaining adequate thermal contact between the heater and the sides of the borehole are eliminated. Using this method downhole measurements were obtained and favorably compared with laboratory measurements on characterized core specimens taken from wells in a hot dry rock geothermal reservoir.

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