Optical Video Disk Recorder with Large Storage Capacity using Small Size Phase-Change Media

This study presents the energy storage potential of nitrate salts for specific applications in energy systems that use renewable resources. For this, the thermal, chemical, and morphological characterization of 11 samples of nitrate salts as phase change materials (PCM) was conducted. Specifically, sodium nitrate (NaNO3), sodium nitrite (NaNO2), and potassium nitrate (KNO3) were considered as base materials; and various binary and ternary mixtures were evaluated. For the evaluation of the materials, differential Fourier transform infrared spectroscopy (FTIR), scanning calorimetry (DSC), thermogravimetric analysis (TGA), and scanning electron microscopy (SEM) to identify the temperature and enthalpy of phase change, thermal stability, microstructure, and the identification of functional groups were applied. Among the relevant results, sodium nitrite presented the highest phase change enthalpy of 220.7 J/g, and the mixture of 50% NaNO3 and 50% NaNO2 presented an enthalpy of 185.6 J/g with a phase change start and end temperature of 228.4 and 238.6 °C, respectively. This result indicates that sodium nitrite mixtures allow the thermal storage capacity of PCMs to increase. In conclusion, these materials are suitable for medium and high-temperature thermal energy storage systems due to their thermal and chemical stability, and high thermal storage capacity.

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Novel facile self-assembly approach to construct graphene oxide-decorated phase-change microcapsules with enhanced photo-to-thermal conversion performance

Journal of Materials Chemistry A ◽

10.1039/c8ta00215k ◽

2018 ◽

Vol 6 (10) ◽

pp. 4535-4543 ◽

Cited By ~ 33

Author(s):

Kunjie Yuan ◽

Jian Liu ◽

Xiaoming Fang ◽

Zhengguo Zhang

Keyword(s):

Graphene Oxide ◽

Phase Change ◽

Self Assembly ◽

Storage Capacity ◽

Heat Storage ◽

Thermal Conversion ◽

Thermal Reliability ◽

Encapsulation Rate ◽

Large Heat ◽

Conversion Performance

Novel self-assembled phase change microcapsule exhibits high encapsulation rate, large heat storage capacity, good thermal reliability and enhanced photo-thermal performance.

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Hierarchically Porous PVA Aerogel for Leakage-Proof Phase Change Materials with Superior Energy Storage Capacity

Energy & Fuels ◽

10.1021/acs.energyfuels.9b04212 ◽

2020 ◽

Vol 34 (2) ◽

pp. 2471-2479 ◽

Cited By ~ 4

Author(s):

Li Yang ◽

Jie Yang ◽

Li-Sheng Tang ◽

Chang-Ping Feng ◽

Lu Bai ◽

...

Keyword(s):

Energy Storage ◽

Phase Change ◽

Phase Change Materials ◽

Storage Capacity ◽

Hierarchically Porous ◽

Energy Storage Capacity

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Thermal Storage Capacity and Night Ventilation Performance of a Solar Chimney Combined with Different PCMs

International Journal of Photoenergy ◽

10.1155/2017/8363190 ◽

2017 ◽

Vol 2017 ◽

pp. 1-10 ◽

Cited By ~ 1

Author(s):

Jun Lu ◽

Xiaolong Gao ◽

Qianru Li ◽

Yongcai Li

Keyword(s):

Phase Change ◽

Storage Capacity ◽

Thermal Storage ◽

Airflow Rate ◽

Solar Chimney ◽

Lower Phase ◽

Phase Change Temperature ◽

Study Results ◽

Change Temperature ◽

Night Ventilation

Thermal storage capacity and airflow rate of a solar chimney combined with different PCMs are numerically studied during nighttime. PCMs with phase change temperatures of 38°C, 44°C, 50°C, and 63°C are selected in this numerical study. Results show that the maximum average ventilation rate of 610 kg/m2 and maximum thermal storage of 4750 kJ/m2 are achieved at the phase change temperature of 38°C. However, for phase change temperature of 63°C, night ventilation does not occur under the identical conditions. The findings reveal that a lower phase change temperature can increase the chargeability (and therefore the dischargeability) of a solar chimney, since a higher phase change temperature demands higher solar radiation intensity and longer charging time for a solar chimney. For PCM with a phase change temperature of 44°C, most of the heat stored in PCM is lost to ambient through glass cover by radiation and only a small portion is used for heating the air within air channel.

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PHASE-CHANGE MATERIAL: NATURAL RUBBER COMPOSITES FOR HEAT STORAGE APPLICATIONS

Rubber Chemistry and Technology ◽

10.5254/rct.19.81468 ◽

2020 ◽

Vol 93 (1) ◽

pp. 208-221 ◽

Cited By ~ 1

Author(s):

Minna Poikelispää ◽

Sasu Ruokangas ◽

Mari Honkanen ◽

Minnamari Vippola ◽

Essi Sarlin

Keyword(s):

Natural Rubber ◽

Phase Change ◽

Thermal Energy ◽

Elevated Temperatures ◽

Storage Capacity ◽

Heat Storage ◽

Damping Properties ◽

Rubber Composites ◽

Good Ability ◽

Natural Rubber Composites

ABSTRACT Global warming and environmental awareness in general have increased the research into thermal energy storage fields. Phase-change materials (PCMs) are efficient in storing thermal energy because of their high latent heat during the phase change. As the phase change is often based on the melting of the PCM, they need to be encapsulated, for example, by dispersing the PCM to a polymer matrix. In this study, the feasibility of the use of paraffin–natural rubber composites in applications requiring both the good ability to store heat energy and good vibration-damping properties is studied. This includes studies on PCM concentration and the microencapsulation of the PCM. It was found that the heat storage capacity increases with increasing PCM content, although the theoretical maximum capacity is not achieved because the PCM is released during vulcanization and the paraffin blooms. In addition, the loss factor was found to be increased at elevated temperatures, indicating improved damping properties. The encapsulation of PCM is found to have a positive influence on the heat storage capacity and the mechanical and damping properties of the rubber compound.

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