Interstitial Air Pressure Dependence of Effective Thermal Conductivity and Diffusivity of Rajasthan Desert Sand Using Transient Hot-Strip Method

Abstract

The transient hot strip (T H S) method used for the simultaneous measurement of effective thermal conductivity and diffusivity of loose granular two-phase materials at normal pressure and room temperature is now used for the measurement of effective thermal conductivity and diffusivity of Rajasthan Desert sand at different interstitial air pressure and room temperature. Experimental values of effective thermal conductivities and diffusivities at different interstitial air pressures have been compared with the estimated values using empirical models for the variation of thermal conductivity and diffusivity with interstitial air pressures. Estimated values are in good agreement with the experimental results in the interstitial air pressure range from 1 mm to 760 mm of mercury, whereas in the low pressure range (0.1 mm to 1 mm Hg) deviations from the experimental results have been observed.