For example, Das and co-workers [6–8] found reduced SHCs of nanofluids consisting of silicon dioxide, zinc oxide, and alumina NPs, respectively, dispersed in a mixture of water and ethylene glycol as compared to that of the base fluid. Meanwhile, the SHC of the nanofluid decreases with increasing NP concentration. Zhou and Ni  also found a reduced SHC
of the water-based alumina nanofluid, and a similar decrease of SHC with increasing particle concentration was observed. In contrast, Zhou et al.  found a maximum of 6.25% enhancement of the SHC of the ethylene glycol-based CuO nanofluid. In addition, 4EGI-1 purchase Shin and Banerjee [11, 12] obtained 14.5% and 19% to 24% enhancements of the SHCs in the nanofluids consisting of 1-wt.% SiO2 NPs doped in Li2CO3-K2CO3 eutectic and chloride eutectic, respectively. Besides, studies [6, 10–12] also selleck compound found a large discrepancy between their
experimental results and the predictions from the existing model : (1) where the subscripts nf, np, and f denote nanofluid, NP, and solvent, respectively, and c p, ϕ, and ρ are SHC, volume fraction, and density, respectively. In this work, we investigate SHCs of molten salt-doped with alumina NPs. The material selected is because of the fluid utilized as a heat storage medium in the solar-thermal power plants, and the SHC of it determines energy storage capacity Methane monooxygenase in the power plants. Here, the effect of NP addition on the SHC of the molten salt and the underlying mechanisms were
examined. buy AZD2171 Furthermore, a theoretical model supporting the experimental results was proposed. Methods The nanofluids were synthesized by introducing various concentrations of the alumina NPs with two nominal sizes of 13 and 90 nm (bought from Sigma-Aldrich, St. Louis, MO, USA) into the molten salt consisting of 60-wt.% NaNO3 and 40-wt.% KNO3 (i.e., solar salt ). The method of nanofluid synthesis is similar to that adopted by Shin and Banerjee . Figure 1 shows the procedure of nanofluid synthesis. First, a mixture of salt (60-wt.% NaNO3 and 40-wt.% KNO3) and alumina NPs with specified concentration was prepared in a beaker. Second, the same weight of deionized (DI) water was then added into the beaker. Third, the solution was mixed up in an ultrasonic for 100 min. Forth, the DI water was evaporated by heating the solution on a hot plate at 105°C for 12 h. Finally, the well-mixed mixture consisting of the molten salt doped with NPs was melted at 300°C for 40 min in a high-temperature oven. Accordingly, the molten salt-based alumina nanofluid can be obtained. Figure 1 Nanofluid synthesis.