Thermal Conductivity of Standard Sands. Part I. Dry-State Conditions

A comprehensive thermal conductivity (λ) database of three dry standard sands (Ottawa C-109, Ottawa C-190, and Toyoura) was developed using a transient line heat source technique. The database contains λ data representing a variety of soil compactions and temperatures (T) ranging from 25 °C to 70 °C. The tested standard sands, due to their repeatable physical characteristics, can be used as reference materials for validation of thermal probes applied to similar dry granular materials. The measured data show an increasing trend of thermal conductivity at dryness (λdry) against T in spite of declining quartz λ with T. The air content (porosity) controls the λ of dry sands by acting as a very effective thermal insulator around solid soil particles. As a result, a diminutive increase of λdry with T is driven by increasing λ of air. The experimental λ data of dry sands were exceptionally well predicted by de Vries and Woodside–Messmer models, and also by a thermal conductance model, a product of λ of solids and the thermal conductance factor.

[1]  Krishpersad Manohar,et al.  Measurement of apparent thermal conductivity by the thermal probe method , 2000 .

[2]  Aj Peck,et al.  On the Cylindrical Probe Method of Measuring Thermal Conductivity with Special Reference to Soils. I. Extension of Theory and Discussion of Probe Characteristics , 1958 .

[3]  W. Woodside,et al.  Thermal Conductivity of Porous Media. II. Consolidated Rocks , 1961 .

[4]  W. Woodside,et al.  Thermal Conductivity of Porous Media. I. Unconsolidated Sands , 1961 .

[5]  D. D. Vries,et al.  CHAPTER 2 – The Physics of Plant Environments , 1963 .

[6]  D. Evans,et al.  Thermal conductivity and diffusivity of soil using a cylindrical heat source. , 1970 .

[7]  I. Sakaguchi,et al.  Decrease in thermal conductivity with increasing temperature in nearly dry sandy soil , 2007 .

[8]  Masanobu Oda,et al.  EXPERIMENTAL STUDY OF ANISOTROPIC SHEAR STRENGTH OF SAND BY PLANE STRAIN TEST , 1978 .

[9]  J. C. Jaeger,et al.  Conduction of Heat in Solids , 1952 .

[10]  W. Woodside,et al.  HEAT AND MOISTURE TRANSFER IN CLOSED SYSTEMS OF TWO GRANULAR MATERIALS , 1959 .

[11]  A. Eucken,et al.  Allgemeine Gesetzmäßigkeiten für das Wärmeleitvermögen verschiedener Stoffarten und Aggregatzustände , 1940 .

[12]  T. Kasubuchi,et al.  Effect of reduced air pressure on soil thermal conductivity over a wide range of water content and temperature , 2002 .

[13]  K. Horai,et al.  Thermal conductivity of rock‐forming minerals , 1971 .

[14]  P. Robertson,et al.  Void ratio redistribution in undrained triaxial extension tests on Ottawa sand , 1998 .

[15]  Predicting effective thermal conductivities of unbonded and bonded silica sands , 1999 .

[16]  D. Vries.  Thermal properties of soils , 1963 .

[17]  Marios Sophocleous,et al.  Analysis of water and heat flow in unsaturated‐saturated porous media , 1979 .

[18]  J. Santamarina,et al.  Fundamental study of thermal conduction in dry soils , 2008 .

[19]  W. O. Smith.  THE THERMAL CONDUCTIVITY OF DRY SOIL , 1942 .

[20]  Richard McGaw.  HEAT CONDUCTION IN SATURATED GRANULAR MATERIALS , 1969 .

[21]  O. Johansen.  Thermal Conductivity of Soils , 1977 .

[22]  Gaylon S. Campbell,et al.  Soil thermal conductivity , 1990 .

[23]  W. O. Smith,et al.  The Thermal Conductivity of Dry Soils of Certain of the Great Soil Groups , 1939 .

[24]  V. E. Sweat,et al.  Analysis of various design and operating parameters of the thermal conductivity probe , 1996 .

[25]  J. Sengers,et al.  Improved International Formulations for the Viscosity and Thermal Conductivity of Water Substance , 1986 .

[26]  Siegmund Brandt,et al.  Statistical and Computational Methods in Data Analysis , 1971 .