Heat Transfer Enhancement of Phase Change Materials for Thermal Energy Storage Systems

2019 ◽  
Author(s):  
Celine S. L. Lim ◽  
Ryan Weaver ◽  
Sarvenaz Sobhansarbandi
Keyword(s):  
Heat Transfer ◽  
Energy Storage ◽  
Melting Point ◽  
Thermal Performance ◽  
Thermal Energy ◽  
Phase Change Materials ◽  
Silicone Oil ◽  
Storage Systems ◽  
Transfer Enhancement ◽  
Thermal Energy Storage Systems

Abstract Solar water heaters (SWHs) are a well-established renewable energy technology that have been widely adopted around the world. The downfall of this technology is rooted in the inconsistency of solar intensity from day to night. In the recent studies, the application of energy storage materials such as phase change materials (PCMs) has attracted many attentions; however, PCM by itself may not be effective due to the poor heat transfer rate, low thermal diffusivity and thermal conductivity. This paper aims to explore the thermal performance of energy storage-transfer materials to be applied in conjunction with PCMs. The selected types of PCMs are paraffin waxes with melting point temperatures of 28–72°C. In the first analysis, silicone oil is selected as the heat transfer medium with high thermal stability. The melting point and specific heat capacity were measured by a modulated differential scanning calorimeter (MDSC). The obtained results show that silicone oil will lead to melting point depression of maximum 3°C in the PCMs. In the second analysis, the heat transfer enhancement by addition of nanoparticles has been investigated. The selected nanoparticles for this analysis are Aluminum Oxide (Al2O3) and Cupric Oxide (CuO). The obtained results from this study show thermal performance improvement of the PCMs which can be applied to different thermal energy storage systems, such as in the case of solar thermal collectors for the application in SWH technology.

scholarly journals Investigation of the dynamic characteristics of a thermal energy storage unit filled with multiple phase change materials

2018 ◽  
Vol 22 (Suppl. 2) ◽  
pp. 527-533 ◽  
Author(s):  
Xiaoyan Li ◽  
Rongpeng Huang ◽  
Xinyue Miao ◽  
Xuelei Wang ◽  
Yabin Liu ◽  
...  
Keyword(s):  
Heat Transfer ◽  
Energy Storage ◽  
Phase Change ◽  
Thermal Energy ◽  
Thermal Energy Storage ◽  
Phase Change Materials ◽  
Storage Systems ◽  
Heat Transfer Fluid ◽  
Energy Storage Systems ◽  
Thermal Energy Storage Systems

In order to improve the thermal performance of thermal energy storage systems, a packed bed thermal energy storage systems unit using spherical capsules filled with multiple phase change materials (multi-PCM) for use in conventional air-conditioning systems is presented. A 3-D mathematical model was established to investigate the charging characteristics of the thermal energy storage systems unit. The optimum proportion between the multi-PCM was identified. The effects of heat transfer fluid-flow rate and heat transfer fluid inlet temperature on the liquid phase change materials volume fraction, charging time and charging capacity of the thermal energy storage system unit are studied. The results indicate that the charging capacity of multi-PCM units is higher than that of the conventional single-PCM (HY-2). For proportions 0:1:0, 2:3:3, 3:2:3, 3:3:2, 4:1:3, and 4:2:2, the charging capacity decreases by approximately 24.84%, 14.69%, 6.47%, 3.82%, and 1.13%, respectively, compared to the 4:2:2 proportion. Moreover, decreasing the heat transfer fluid inlet temperature can obviously shorten the complete charging time of the thermal energy storage systems unit.

scholarly journals Nano-Enhanced Phase Change Materials in Latent Heat Thermal Energy Storage Systems: A Review

Energies ◽  
2021 ◽  
Vol 14 (13) ◽  
pp. 3821
Author(s):  
Kassianne Tofani ◽  
Saeed Tiari
Keyword(s):  
Energy Storage ◽  
Phase Change ◽  
Latent Heat ◽  
Thermal Energy ◽  
Thermal Energy Storage ◽  
Phase Change Materials ◽  
Storage Systems ◽  
Heat Pipes ◽  
Energy Storage Systems ◽  
Thermal Energy Storage Systems

Latent heat thermal energy storage systems (LHTES) are useful for solar energy storage and many other applications, but there is an issue with phase change materials (PCMs) having low thermal conductivity. This can be enhanced with fins, metal foam, heat pipes, multiple PCMs, and nanoparticles (NPs). This paper reviews nano-enhanced PCM (NePCM) alone and with additional enhancements. Low, middle, and high temperature PCM are classified, and the achievements and limitations of works are assessed. The review is categorized based upon enhancements: solely NPs, NPs and fins, NPs and heat pipes, NPs with highly conductive porous materials, NPs and multiple PCMs, and nano-encapsulated PCMs. Both experimental and numerical methods are considered, focusing on how well NPs enhanced the system. Generally, NPs have been proven to enhance PCM, with some types more effective than others. Middle and high temperatures are lacking compared to low temperature, as well as combined enhancement studies. Al2O3, copper, and carbon are some of the most studied NP materials, and paraffin PCM is the most common by far. Some studies found NPs to be insignificant in comparison to other enhancements, but many others found them to be beneficial. This article also suggests future work for NePCM and LHTES systems.

Sign in / Sign up

Export Citation Format

Share Document