Heat transfer characteristics of impinging jet on a hot surface with constant heat flux using Cu2O–water nanofluid: An experimental study

The experimental investigations are carried out on a circular nanofluid jet impingement for cooling an aluminum disk with constant heat flux. The study is performed to understand the effects of different factors such as Reynolds number and nanoparticle concentration on the fluid flow and characteristics of heat transfer. The target surface has a circular shape and is kept at constant heat flux with the value of 1414.71 W/m2. The copper oxide-nanoparticle concentrations are changed from 0.03 to 0.07 wt%. The experimental results show that the Cu2O nanofluid increases the heat transfer efficiency of the impinging jet cooling system. Compared to the case of using the base fluid, the nanofluid increases the convective heat transfer by 45% at 0.07 wt% concentration at Reynolds number of 7330. The center of the target surface, i.e. the stagnation zone, has the highest turbulence intensity because of impinging of the fluid flow on the surface center, while the endpoint of the target surface has the minimum turbulence intensity. Indeed, the turbulence intensity decreases along the radial direction, which augments the effect of employing the nanofluid because the heat transfer due to the turbulence diminishes and merit of using the nanofluid enhances.