抄録
The guarded hot plate (GHP) method is the most popular way of measuring thermal conductivity of thermal insulations. However, there are large differences among the thermal conductivities measured by different GHP apparatuses which are made in different institutions in the temperature range above 100 ℃. It must be the reason why GHP apparatuses have complex structures for realizing the principle of the GHP method. In this study, the new estimation method for thermal conductivity was proposed, when using the GHP method. This method makes use of heat losses from side surfaces of the specimen. It was assumed that the heat generated in the metering section heater separates into two heats in the directions of thickness and plane of the specimen. Then, the relationship between the measured thermal conductivity λ and the estimated one λ_t in the direction of thickness was derived. By using this relationship, the thermal conductivityλ_t, in the direction of thickness was determined.
