DETERMINATION OF THERMAL CONDUCTIVITY OF SODIUM NITRATE AT THE LIQUID/SOLID PHASE TRANSITION POINT

摘要

The theory that the thermal conductivity could be obtained by measuring the speed of the movable solid/liquid phase interface during the phase transition had been successfully used to determine the thermal conductivity of metals at the liquid/solid phase change point. And a series of verification experiments had been performed to test the feasibility of application of the same theory and the modified measuring system to determination of thermal conductivity of molten salts which were widely used as high-temperature phase-change materials. This research carried out the experiment to investigate the thermal conductivity of sodium nitrate. At the same time the mathematical method was applied to intuitively simulate the melting process in the phase change chamber, through which the error could be analyzed and partly corrected and the measuring system could be modified in order to increase the result precision. The error of the result is within 6%.