Modelling of Cooling Rate of Clays: An Example of Indirect Evaluation of Heat Capacity and Storage

Abstract

We investigated how compacted samples of Ca-bentonite and kaolin cool down when exposed to room air after oven drying to understand whether we can constrain their thermal conductivity and heat capacity. We evaluated the effect of porosity on the cooling rate and used a simple numerical model of heat transfer to obtain the sought-after parameters. Our laboratory results show that both soils exhibit sudden cooling behavior, which can play a crucial role in identifying thermal conductivity and other thermal parameters of soil samples. Our approach provided reasonable values for both thermal conductivity and heat capacity. The latter, however, exhibits much larger sensitivity to porosity and can therefore be constrained better. Further experiments are required to establish a standardized procedure and evaluate the response of different materials. Nevertheless, our approach could prove useful for empirically calibrating thermal parameters in advanced constitutive models.