Numerical investigation of heat transfer characteristics for blood/water-based hybrid nanofluids in free convection about a circular cylinder

Abstract

This paper investigates hybrid nanofluids flowing around a circular cylinder of free convection under the constant surface heat flux.  Nanoparticles of copper oxides, Gold, and Aluminum (CuO, Au, Al) are considered to support the heat transfer performance of blood/water-based hybrid nanofluids. The governing model for hybrid nanofluids which is in form of non-linear partial differential equations (PDEs) are first transformed to a more convenient form by similarity transformation approach then approximated numerically by the Keller box method. Several comparatives are performed in this work resulting in the superiority of the hybrid-nanofluid over regular nanofluid in terms of heat transfer rate, velocity, and local skin friction coefficient.  Findings confirmed that the surface temperature and temperature field are augmented, with increasing volume fraction for nanoparticles. Also, Gold nanoparticles give a higher result for all examined physical properties than Aluminum and copper oxides nanoparticles.