Improving the thermal charging rate of latent heat thermal energy storage systems is essential for high-temperature applications such as concentrated solar power. In this study, buoyancy-driven melting of solar salt enhanced with ternary hybrid nanoparticles is numerically investigated in a differentially heated cavity with localized heating. Three nanoparticle combinations are examined at volume fractions up to 5%. The results indicate that melting initiates under conduction near localized heat sources, followed by convection-dominated transport that accelerates phase change. The addition of ternary hybrid nanoparticles enhances effective thermal conductivity, leading to faster melting and improved heat transfer. Increasing nanoparticle concentration consistently improves system performance. Among the configurations, the SiO 2 –CuO–SWCNT combination exhibits the highest enhancement, achieving up to 25.6% reduction in total melting time compared to pure solar salt. The enhanced thermal transport also results in increased heat storage rate and higher Nusselt number, indicating strengthened convective heat transfer. The ternary hybrid nano-enhanced solar salt demonstrates improved thermal charging performance under localized heating conditions. • Numerical study of ternary hybrid nano-enhanced solar salt melting. • Investigation under localized heating capturing conduction-to-convection melting transition. • Achieves up to 25.6% reduction in total melting time compared to pure solar salt. • Nusselt number enhanced by nearly 40% at higher Rayleigh number and nanoparticle loading. • SiO 2 -CuO-SWCNT combination exhibits superior thermal transport and energy storage performance.
Shaneesh et al. (2026) studied this question.