Abonnement à la biblothèque: Guest

ISSN Online: 2377-424X

ISBN Print: 978-1-56700-474-8

ISBN Online: 978-1-56700-473-1

International Heat Transfer Conference 16
August, 10-15, 2018, Beijing, China

SOLIDIFICATION HEAT TRANSFER CHARACTERISTICS OF PHASE CHANGE EMULSION IN TURBULENT FLOW REGION

Get access (open in a dialog) DOI: 10.1615/IHTC16.ecs.023186
pages 4343-4349

Résumé

A phase change emulsion (PCE) is a mixture of an aqueous surfactant solution and fine particles of a phase change material (PCM) dispersed inside it. Size of PCM particles inside PCEs are 0.1 − 10 µm, so PCEs keep homogeneous state for long time. Furthermore, PCE offers high thermal storage density utilizing latent heat of PCM. Thus, PCEs have been attracting attention as a novel thermal medium. However, heat transfer characteristics of PCEs have not been studied sufficiently yet. To use PCEs as thermal media, their heat transfer characteristics must be known. In this study, solidification heat transfer characteristics of PCE was investigated assuming heat storage in PCE using heat exchanger. PCE was prepared by mechanical emulsification and n-hexadecane (melting point 18.2 °C) was used as the PCM. PCE was cooled using double-tube type heat exchanger and flow through the inner tube under turbulent flow condition. In the experiment, Reynolds number of PCE and the brine and temperature difference between PCE and the brine were varied as the experimental parameter. As the experimental result, it was confirmed that the heat storage amount of PCM inside PCE increased with the cooling distance and the temperature of PCE was kept at solidification starting point of dispersed PCM when the solidification of PCM started. Furthermore, when solidification of PCM was accompanied, the mean heat transfer coefficient of PCE increased as compared with the case without solidification of PCM and increase rate of the mean heat transfer coefficient depended on the solidification amount of PCM.