Reproducibility of solidification and melting processes in a latent heat thermal storage tank

Abstract

Elsevier Bosholm, F.; López Navarro, A.; Gamarra, M.; Corberán Salvador, JM.; Payá Herrero, J. (2016). Reproducibility of solidification and melting processes in a latent heat thermal storage tank. International Journal of Refrigeration. 62:85-96. AbstractThis study analyses the reproducibility of solidification and melting tests in a tank containing 181 kg of paraffin for cold storage at around 8ºC. Firstly, an experimental campaign of 10 identical tests was carried out. The performance is practically the same in terms of PCM temperatures and thermal power, with a maximum deviation of 2% in the capacity of all tests. In a second campaign, the impact of the initial conditions was studied. The results indicate that fixing a same mean PCM temperature at the beginning of the tests is insufficient to ensure an accurate reproducibility. Depending on the heat transfer rate during the preparation tests, the capacity differed in up to 33%. In tanks with such quantities of PCM, fixing a uniform initial PCM temperature is hardly possible, thus it is important to prepare the tank with same operation conditions.

Development of cooling systems on the basis of absorption water-ammonia refrigerating machines of low refrigeration capacity

“…In Australia [34], the cost of the cooling system was attempted to be reduced by combining the NRC system with solar panels (photovoltaic panels).…”

“…In all studies [32][33][34], in the daytime, cooling of the radiator (cooling device) below the outdoor temperature was not achieved, because the absorbed solar energy exceeded the radiated thermal radiation.…”

“…Thus, the works of researchers [28][29][30][31][32][33][34][35][36][37][38] show the energy efficiency of the NRC technology for objects of passive heat dissipation into the surrounding atmospheric air.…”

Development of cooling systems using the night-radiation effect

“…Также для улучшения результата, предлагается радиатор закрыть полиэтиленовой пленкой для снижения конвективного теплопритока и покрасить его поверхность краской с высокой излучательной способностью [7], чтобы он мог отдавать большее количество тепла за счет инфракрасного излучения. Однако радиационное охлаждение в основном было осуществимо только в ночное время, поскольку подходящие материалы с высокой инфракрасной излучательной способностью не обеспечивали охлаждения в дневное время [13,14]. В качестве красителя, в частности, предлагается использовать материал с большим содержанием соединения ТiO2, что повышает излучательную способность поверхности [15].…”

Fundamental melting process of water-insoluble phase change material immersed in water

“…However, it is rarely adopted because waste heat cannot be used without thermal energy storage (TES) technologies, which are available for long distance transport or long-term storage. Latent heat storage (LHS) is an example of a TES technology, which can store large amounts of thermal energy using the latent heat of a phase change material (PCM) (Yamada et al, 2006, Nomura et al, 2010, Veerakumar et al, 2016, Bosholm et al, 2016. In general, the latent heat of solidification and melting are used in LHS devices.…”