ABSTRACTWe determined values of thermal conductivity for Berino sand packed into columns, using the line heat source method described by de Vries (1952a). The microwave oven technique of Horton et al. (1982) was used to bring the soil in the columns to a predetermined water content. We then compared our measured values of thermal conductivity with those measured in columns packed with premoistened soil (Westcot 1972). At water contents below 0.10 cm3/cm3, we found poor agreement between the values of thermal conductivity, which we attributed to the manner in which columns were packed with soil. Columns with larger bulk density were found to have substantially larger values of thermal conductivity in the range of water contents from ovendry to 0.10 cm3/cm3.We also compared our measured values of thermal conductivity with values calculated using the method described by de Vries (1963). There was better agreement between our measurements and the calculations than was found by Westcot (1972). In both cases, however, the agreement was relatively poor. When we used the shape factors for air or solids similar to those of Kimball et al. (1976), the agreement between calculated thermal conductivity and values measured in this study improved.
We determined values of thermal conductivity for Berino sand packed into columns, using the line heat source method described by de Vries (1952a). The microwave oven technique of Horton et al. (1982) was used to bring the soil in the columns to a predetermined water content. We then compared our measured values of thermal conductivity with those measured in columns packed with premoistened soil (Westcot 1972). At water contents below 0.10 cm3/cm3, we found poor agreement between the values of thermal conductivity, which we attributed to the manner in which columns were packed with soil. Columns with larger bulk density were found to have substantially larger values of thermal conductivity in the range of water contents from ovendry to 0.10 cm3/cm3.
We also compared our measured values of thermal conductivity with values calculated using the method described by de Vries (1963). There was better agreement between our measurements and the calculations than was found by Westcot (1972). In both cases, however, the agreement was relatively poor. When we used the shape factors for air or solids similar to those of Kimball et al. (1976), the agreement between calculated thermal conductivity and values measured in this study improved.
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