Mechanism of heat capacity enhancement in molten salt nanofluids

摘要

Recent studies (Shin et al., 2014; Tiznobaik and Shin, 2013) in molten salt nanofluids have discussed the possibility of the development of nano dendritic structures as a mechanism behind heat capacity enhancements. It is established that these nanostructures enhance heat capacity due to their increased surface area. Shin et al. explained that these structures might be resulting from micro-segregation in salt eutectic due to differences in the level of attraction between different types of salts and nanoparticles. However, it does not explain how this segregated salt develops into dendrites. In this study, Tiznobaik's work is further exploited and explained based on nucleation and grain growth of nucleated salt. It is proposed that segregated nucleate on the surface of nanoparticles via heterogeneous nucleation and grow into dendritic through single-dimensional grain growth. Experimental verification for heat capacity enhancement performed on differential scanning calorimeter (DSC). Transmission electron miscroscope (TEM) was employed imaging dendritic strcutures.