THERMOPHYSICAL PROPERTIES OF A SLURRY OF DISTILLED WATER AND MICROENCAPSULATED PHASE-CHANGE MATERIALS

摘要

This paper presents experimental measurements of some effective thermophysical properties of slurries consisting of microencapsulated phase change materials (MCPCMs) suspended in distilled water. The related apparatus and procedures are also presented and discussed. The MCPCMs considered here consist of a core of phase-change material (PCM), in this case a substance akin to octadecane, surrounded by a solid shell. The effective density of the slurries was measured using hydrometers. The effective thermal conductivity of the slurries was measured using an in-house designed apparatus. The effective kinematic viscosity of the slurries was measured using a series of glass capillary viscometers. A differential scanning calorimeter (DSC) was used to obtain the effective specific heat, melting and freezing temperatures of the core PCMs, and the latent heat of the slurries. Slurry concentrations between 0% (pure distilled water) and 20% by mass of the MCPCMs were considered in this investigation, at temperatures ranging from 5℃ to 65℃. Where possible, the results have been compared to predictions obtained using available analytical expressions with properties of the constitutive materials as inputs.