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PCM emulsions have attracted considerable interest as the media for thermal energy storage (TES) owing to their high thermal storage capacity, desirable fluidity and thermal conductivity. However, the direct transportation of PCM emulsions in TES systems for both charging and discharging is rarely reported. In this work, a PCM-in-water nano-emulsion was prepared with n-hexadecane and suitable surfactants for cooling energy storage at a charging and discharging temperature range of 20–5 °C and 5–15 °C, respectively. It was applied to a tubular heat exchanger system to evaluate its TES performance for a cooling panel of 0.2 m2 total surface area. The thermal storage performance was notably increased with the flow rate of emulsion through the exchanger tube. The volumetric thermal storage capacity of charging was 50% higher than that of water. The cooling energy could be rapidly released in the discharging process, 79% of the stored energy at averaging 25 W during most of the discharging period. The emulsion remained stable throughout the test period. Overall, the results demonstrated that the PCM nano-emulsion has the unique characteristics of high static stability, and high energy releasing efficiency and the promising potential for air-conditioning application in buildings.

This paper reports the effectiveness ofmetal-cladding (MC) winding technique employing a GdBCO tape with a micrometer-thick stainless-steel clad as experimentally compared with that of the partial insulation (PI) winding technique. The investigation included charge-discharge, sudden-discharge, and overcurrent tests. The charge-discharge and sudden-discharge tests showed that the charge/discharge process of the coil using the metal-clad GdBCO tape was considerably shorter than those of the PI coils, because the effective resistance of the MC coil was higher than those of the PI coils. Although the MC coil exhibited lower electrical stability than the PI coils did (when the current is high enough), the MC coil was virtually more stable than any fully insulated coil. This study confirms that theMC winding technique is promising for the development of electrically stable high-field magnets allowing relatively high rates of ramping up and down. [ABSTRACT FROM AUTHOR]