T-HISTORY ANALYSIS OF ASPECT RATIO EFFECT ON SUBCOOLING AND SOLIDIFICATION BEHAVIOUR OF PHASE CHANGE MATERIAL IN VERTICAL GLASS TUBES

Abstract

The study deals with the effect of the tube aspect ratio on subcooling and the solidification behaviour of phase change material using the T-history method and is compared with the differential scanning calorimetry analysis. Three tubes of different aspect ratios, l/d, and a constant length of 178 mm are chosen for this study. Infrared contour depicts that the inner surface of the glass tube and phase change materia initiate heterogeneous nucleation. The differential scanning calorimetry heat flow graph indicates a higher degree of subcooling than T-history method. The study of aspect ratio with and without insulation shows that the mean value of degree of subcooling is less in the insulated tube than non-insulated tube due to reduced cooling rate. The effect of the high aspect ratio is to increase the degree of subcooling due to increased cooling rate and, however, decrease the sensible heat discharge time to reach the plateau, tplt. © 2022 Society of Thermal Engineers of Serbia. All Rights Reserved.