Investigation of the Thermal Conductivity of Ice.

摘要

Measurement of the thermal conductivity of ice I (the normal phase at atmospheric pressure) over the temperature range 4to 273 K has been attempted. First the linear absolute method was employed in which an adiabatically shielded copper block (1kg) provided an infinitely variable heat-sink temperature with a stability of better than 1 nK/hr. Sublimation precluded adiabatic operation above 175 K;inadequate thermal coupling was apparent below this temperature. Measurements were taken on nylon both to obtain needed data and to confirm the function of the instrument;data is reported over a range of 4to 360 K with an accuracy of 0.6% or better. The cylindrical method was adopted to overcome sublimation and bonding difficulties with ice. This allows positioning of the heating unit and measuring thermocouples within the sample;thus no shielding or hard vacuum is necessary to overcome heat loss problems. The preliminary investigation showed a random scatter of plus or minus 5%. Temperature fluctuations within the refrigerant bath were responsible for most of this scatter. By using an adjustable form factor the data follows a most probable thermal conductivity curve constructed by Morris and Smith (45) from all previously reported data. (Author)