عنوان مقاله [English]
نویسندگان [English]چکیده [English]
Thermal property means the material's response to heat application. When energy (in the form of heat) is absorbed by a solid material, its temperature, and subsequently its dimensions, increase. The energy may be transferred to the cooler regions of the sample and may even melt the sample. The mechanism of heat transfer in rocks is very complicated. Rocks are composed of mineral particles with various chemical compositions and various degrees of crystallization. Therefore, the thermal properties of rocks depend not only on the pressure and temperature, but also on the mineralogical composition, the structure and geometry of pores, the size of the particles and the shapes of cracks. The main thermal properties of rocks include heat capacity, thermal conductivity, thermal diffusivity and thermal expansion, which they are needed for numerical modeling, considering the effects of temperature, including the modeling of oil wells, gas storage caverns, nuclear waste disposal site, and deep mines. In the present study a device for determining one of these properties, the coefficient of thermal expansion, is developed. To evaluate the efficiency of the device, the values of this coefficient in the sandstone, andesite, the green tuffs of the Karaj formation and limestone are determined. The results are consistent with the results of the experimental studies on rocks found in the literature.