Numerical Simulation of Flow and Heat Transfer of Nanofluid around a Heated Square Cylinder

A numerical investigation was conducted to study the forced and mixed convection of nanofluid in a horizontal channel with a built-in-heated square cylinder. The nanofluid considered in this study is composed of metal nanoparticles(Cu) suspended in water (base fluid). The governing equations are solved using the finite volume method based SIMPLER algorithm. Different Reynolds numbers and volume fractions of nanoparticles ranging respectively from Re= 85 to 200 and from [phi]= 0%to12%, have been considered. The effect of the nanoparticles volume fraction on the critical Reynolds number value defining the transition between two flow regimes (stationary and periodic)as well as on the overall flow coefficients is firstly studied. In the thermal study, we have established correlations to evaluate the heat flux transferred from the obstacle to the flow for different nanoparticles volume fractions. Results show a marked improvement in heat transfer compared to the base fluid. This improvement is more pronounced for higher Richardson numbers and higher nanoparticles volume fractions.