【摘要】 以砂子模拟堆积型多孔介质,采用Hot D isk热常数分析仪(TPS 2500)对不同含湿率砂的有效导热系数进行测量和实验研究。研究发现,非饱和含湿砂有效导热系数随含湿率的增加而增大。低含湿率(体积含湿率低于25%)情况下,砂子的有效导热系数难以准确测得,其主要原因是测试过程中,由于加热影响,贴近探头附近的水分因蒸发扩散而逐渐减少,探头周围试样构成不能保持恒定,导致测试环境持续发生变化。更多还原

【Abstract】 Thermal conductivity of unconsolidated porous media with various moisture contents,which was act as by sands,has been measured and studied by a thermal constant analyzer(Hot Disk TPS 2500).The result indicated that thermal conductivity of unsaturated wet unconsolidated porous media increased with the moisture content increasing.Study also showed that the real thermal conductivity was quite difficult to be obtained with low moisture content(less than 25% void space).The main reason is that the water in the sensor adjacent region evaporated due to heating by the sensor.As a result,the properties of this region could not keep invariable,and caused the testing condition varying during the whole measuring period.更多还原