Laser Flash Method for Measuring Thermal Conductivity of Liquids. Application to Molten Salts

Abstract

A new variation of the laser flash method for measuring the thermal conductivity of molten salts was developed. The sample liquid was sandwiched between a thin metal disk and a sample holder without using any liquid container. This ensured one-dimensional heat flow downward through the sample liquid. In this method, the thermal conductivity of liquids could easily be obtained without using any reference materials and without the measurement of the total input heat energy of the laser beam and of the liquid layer thickness. The minor heat loss to the surroundings could easily be obtained experimentally. The data obtained for sodium and potassium nitrates between 320 and 390 °C agree well with those published in the literature. The mean deviation, 3.8%, was only slightly larger than that in the cases of water and toluene near room temperature, 2.6%. This suggests that the present method is suitable for measurement at higher temperatures. © 1981, American Chemical Society. All rights reserved.