Heat transfer analysis of turbulent forced-convection flow in a wavy absorber tube containing a molten salt-based hybrid nanofluid filled with a porous material

Abstract

The thermal performance of turbulent forced-convection flow was investigated in a wavy absorber tube containing a hybrid nanofluid consisting of salt molten filled with a porous material. The nanoparticles dispersed in the working molten salts are Al₂O₃ and graphene, which have a spherical shape and a diameter of less than 100 nm. The assessments were performed under turbulent forced convection flow conditions using k--ε model with enhanced wall treatment. The effects of porous media features, nanoparticle concentrations, and molten salt type on flow, thermal exchange, drop pressure, pumping power, skin friction factor, and efficiency are discussed. Outcomes indicated that boosting the values of increases friction coefficient, drop pressure, pumping power, and and system efficiency. Molten Hitec salt has a lower friction coefficient and pressure loss than Hitec XL and solar salt. The use of solar salt improved the heat transfer rate by and compared to Hitec and Hitec XL, respectively.

Keywords:

• Heat transfer
• nanofluid
• porous material
• turbulence
• wavy absorber