Thermal conductivity of silica gel/water

Measurements of the thermal properties of silica gel were made by making use of a cylindrical apparatus that was intended to be used in experiments under transient and steady-state conditions for different pressures and water contents of the silica. The Bauer-Schlunder (BS) and Kunii-Smith extended (KS*) models have been used to identify the thermal conductivity of silicagel pellets from measurements of the conductivity of a bed in the presence of various gases (temperature 32 degrees C). The transient results were used to identify the thermal diffusivity of the dry beds by means of a numerical solution of the heat-conduction equation. The thermal conductivity of the bed, and of the solid particles, has been found to vary linearly with the water content of the silica gel.