Tunable endothermic plateau for enhancing thermal energy storage obtained using binary metal alloy particles
Authors: Chih-Chung Lai, Shih-Ming Lin, Yuan-Da Chu, Chun-Che Chang, Yu-Lun Chueh, and Ming-Chang Lu
Journals: Nano Energy
Year of Publication: 2016 2016 Impact Factor: 12.343
Abstract Thermal energy storage is crucial for various industrial systems. Enhancements in energy storage induced by latent heat have been demonstrated by using phase-change materials. However, these enhancements occur only at the melting points of the materials. In this study, we demonstrated the controllability of latent heat absorption/release in a certain temperature range. A wide endothermic plateau from 370 to 407 °C for the Hitec salt was obtained by releasing the latent heat of alloy particles embedded in the salt. The alloy particle-doped salt was applied to a Stirling engine to demonstrate its effectiveness in enhancing the energy and power outputs of the engine. Compared to pure salt, the alloy particle-doped salt can enhance the engine's energy output by 21%. With the advantages of scalable synthesis and superior thermal properties, the alloy particles have potential applications in energy storage enhancement in various thermal energy systems.
A solar-thermal energy harvesting scheme: enhanced heat capacity of molten HITEC salt mixed with Sn/SiOxcore–shell nanoparticles
Authors: Chih-Chung Lai, Wen-Chih Chang, Wen-Liang Hu, Zhiming M. Wang, Ming-Chang Lu and Yu-Lun Chueh
Journals: Nanoscale
Year of Publication: 2016 2016 Impact Factor: 7.367
Abstract We demonstrated enhanced solar-thermal storage by releasing the latent heat of Sn/SiOx core–shell nanoparticles (NPs) embedded in a eutectic salt. The microstructures and chemical compositions of Sn/SiOx core–shell NPs were characterized. In situ heating XRD provides dynamic crystalline information about the Sn/SiOx core–shell NPs during cyclic heating processes. The latent heat of ∼29 J g−1 for Sn/SiOx core–shell NPs was measured, and 30% enhanced heat capacity was achieved from 1.57 to 2.03 J g−1 K−1 for the HITEC solar salt without and with, respectively, a mixture of 5% Sn/SiOxcore–shell NPs. In addition, an endurance cycle test was performed to prove a stable operation in practical applications. The approach provides a method to enhance energy storage in solar-thermal power plants.
Specific heat capacity of molten salt-based alumina nanofluid
Authors: Ming-Chang Lu and Chien-Hsun Huang
Journals: Nanoscale Research Letters
Year of Publication: 2013 2016 Impact Factor: 2.833
Abstract There is no consensus on the effect of nanoparticle (NP) addition on the specific heat capacity (SHC) of fluids. In addition, the predictions from the existing model have a large discrepancy from the measured SHCs in nanofluids. We show that the SHC of the molten salt-based alumina nanofluid decreases with reducing particle size and increasing particle concentration. The NP size-dependent SHC is resulted from an augmentation of the nanolayer effect as particle size reduces. A model considering the nanolayer effect which supports the experimental results was proposed.