Computational fluid dynamics and experimental study of the effect of inclination angle on turbulent natural convection in an upward open cubic cavity

The effect of inclination angle on heat transfer by turbulent natural convection in an inclined open cubic cavity with side length of 1m is experimentally and numerically studied. The wall opposite to the aperture is subjected to uniform heat flux condition with a value of 110W/m2, whereas the remaining walls were kept thermally insulated. Six most used two equations turbulence models were tested, with Computational Fluid Dynamics (CFD) software ANSYS FLUENT. The results were obtained for four inclination angle values: 0°, 15°, 30° and 45°. The spatial distribution for temperature, flow pattern and magnitude of velocity are determined and analyzed. An experimental prototype was built to obtain experimental temperature profiles and heat transfer coefficients. The experimental average Nusselt number increases as the inclination angle increases, having a minimum of 203 for 0° case and a maximum of 225 for 45° case. The comparison between experimental and numerical average Nusselt numbers indicates that the minimum average difference is with the realizable κ-ϵt turbulence model, therefore, this turbulence model is recommended to model this type of systems.