Abstract
A thermal conductivity measuring apparatus using both the Guarded Hot Plate (GHP) method and the Cyclic Heat method was designed, and thermal conductivity of a fibrous insulations were measured in atmospheric conditions and in evacuated conditions at temperature range from 100 to 1300°C. When the apparatus using the GHP method was designed, the sizes of the meter and guard heater are determined using the theory by William Woodside. In the Cyclic heat method apparatus, the error magnitude due to difference in period of heat wave was examined, and the time lag method was compared with the amplitude decay method.
The thermal conductivities of the fibrous insulations (aluminum-silica) of both the GHP method and the Cyclic Heat method are in good agreement. This result indicates that values of measurements by the nonsteady state method (Cyclic heat method) is in agreement with the steady state method (GHP method) on proper conditions.
As applied measurement, I compared thermal conductivity of the brick with the fibrous insulation in atmospheric conditions at temperature range from 100 to 1300°C, and examined the relationship between heat flow and different types of fibrous fleeces in a fibrous insulation in evacuated conditions.
