Flow and sedimentation characteristics of silica hard-shell microcapsule slurries treated with additives

The sedimentation and flow characteristics of micro-encapsulated phase change materials have been investigated. As a phase change material, trimethylolethane clathrate hydrate having 218 kJ kg(-1) of latent heat was used and encapsulated in silica hard-shell microcapsules, which size distribution has two peak at 15 mu m and 59 mu m. A cationic surfactant, oleylbishydroxyethylmethylammonium chloride with a counter-ion, sodium salicylate was used as drag reducing additives and poly vinyl alcohol was used as a stabilizer. From the results, it was found that the combination additive prevents effectively the microcapsule sedimentation. The drag reduction was also observed to occur in the high Reynolds number region. Thus, the present additive was concluded to be promising for the latent heat transportation by use of silica hard-shell microcapsules containing phase change materials. (C) 2019 Elsevier Ltd and IIR. All rights reserved.