Using the high-temperature melting-mechanical stirring preparation method
20 nm SiO nanoparticles were uniformly dispersed into a ternary mixed molten salt (KNO-NaNO-NaCO) to prepare molten salt nanofluids containing different mass fractions of SiO nanoparticles (0.1%
0.5%
1.0%
1.5%
2.0%)
in order to investigate the effect of the SiO nanoparticle content on the specific heat capacity and thermal conductivity of the molten salt. A synchronous thermal analyzer and a laser thermal conductivity meter were employed to test and analyze the specific heat capacity and thermal conductivity of both the ternary mixed molten salt and the molten salt nanofluids. Scanning electron microscopy (SEM) was utilized to observe and analyze the microstructure of the samples. The experimental results demonstrate that when the mass fraction of SiO nanoparticles is 1.0%
the average specific heat capacity of the molten salt nanofluid reaches 2.09 J/(g·K)
and the average thermal conductivity reaches 1.073 W/(m·K)
representing increases of 29.6% and 97.9%
respectively
compared to the ternary mixed molten salt. This enhancement is attributed to the formation of a high-density network structure on the surface of the ternary mixed molten salt
which possesses a high specific surface area and surface energy
thereby improving the specific heat and thermal conductivity of the molten salt.
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