A method for measuring thermal conductivity of bentonite

A technique is presented for the determination of thermal conductivity of bentonite. Measurements are performed from the step-wise power supplied to a thermistor probe operated in a self-heated mode. The self-heated thermistor is used to simultaneously heat a specimen and measure the resulting temperature rise of the thermistor. The temperature increase of the thermistor for a given applied power is a function of the combined thermal properties of the thermistor probe and the specimen. Thermal conductivity is determined by the comparison between numerically calculated and measured temperature rises. Measurements can be made in small specimen and perform in a short time. (author)