Deviations from One‐Dimensional Heat Flow in Guarded Hot‐Plate Measurements

摘要: A theoretical analysis is made of the error in thermal conductivity, measured by guarded hot‐plate apparatus, resulting from a temperature difference, or unbalance, between test area and guard ring. The solution obtained application two successive Schwarz transformations, assumptions having been verified relaxation calculations. An expression derived for heat flow specimens. agreement calculated values three different hot plates which experimental data are available 5% better. It therefore now possible to calculate maximum tolerable unbalance achieve any desired accuracy conductivity plate.