Abstract
In this paper, degree of supercooling of phase change material (PCM) of erythritol in a glass tube was investigated for the sample volume from 0.0040 to 16 cm3, the contact area from 0.40 to 28 cm2. The melting point of erythritol is 118 ℃ and the latent heat is 336 J/g. The sample volume and contact area were varied using different diameters of the glass tube from 0.4 to 27 mm. Insoluble particles in the sample were filtered off with pore sizes of 0.7 to 25 µm. In the experiment, the melted erythritol in the glass tube was cooled to 30 ℃ at cooling rate of 0.5 ℃/min. As a result, the degree of supercooling was largely depended on the sample volume and increased significantly with the decrease of volume. In addition, the degree of supercooling increased in the sample filtered with 0.7 µm. These results showed that the inhomogeneous nucleation on the insoluble particle was dominant in the primary nucleation mechanism.
