Synthesis and Characterization of Nano Heat Transfer Fluid (NHTF)

This paper describes a nano-heat transfer fluid (NHTF) consisting of a novel mixture of alkali metal nitrate salt eutectic doped with silica nanoparticles at 0.5% mass concentration with a low melting point, high thermal stability and high specific heat capacity. These properties produce a wide operating range Heat Transfer Fluid and enable effective thermal storage for parabolic trough concentrating solar power plants as compared to present molten salt heat transfer fluids that usually has a high melting point, typically 220°C or higher. This limits its use due to the risk of freezing. The advanced NHTF exploits eutectic behavior with a novel composition of materials and nanoparticles, resulting in a low melting point of 120 °C, a thermal stability limit over 500 °C and an increase in specific heat capacity owing to the presence of suspended silica nanoparticles.