Development of Specific Heat Measuring Apparatus of Geothermal Related Rocks and Their Measurement

岩石比热容的测定有直接法和间接法两种方法。在直接法中，使用差示扫描量热仪。间接法是通过热线法测量导热系数和热扩散系数来计算比热的，直接法存在重复性差的问题。为了解决这一问题，采用了粒径较小的试样和重量在一定范围内的容器。通过这些措施，基线的稳定性有所提高，但重复性不够。在间接法中，成功地测量了室温和400 - 600^C之间的热导率。测量的岩石有花岗岩、安山岩、砂岩、页岩和煤。在热扩散率的测量中，岩石样品和热线之间的接触被发现是最重要的，这将偏离测量温度从理论的初始加热时。在室温下的比热得到了合理的值。

Specific heat of rocks was measured by two different methods, direct method and indirect method. In the direct method, a differential scanning calorimeter was used. In the indirect method, the specific heat was calculated by measuring the thermal conductivity and the thermal diffusivity by using the hot wire method.In the direct method, the bad repeatability was the most significant problem. As for the countermeasure of this problem the specimen with smaller particle size and the vessels, weight of them lie in a certain range, were used. The stability of the baseline was a little bit improved by these measures, but the repeatability was not sufficient.In the indirect method, the thermal conductivity was successfully measured between room temperature and 400 - 600^ﾟC. The measured rocks were granite, andesite, sandstone , shale and coals. In the measurement of the thermal diffusivity, the contact between the rock specimen and the hot wire was found to be the most important , which would deviate the measured temperature from the theoretical one at the time of the initial heating. The specific heat at the room temperature was obtained with a reasonable value.