Solar Air Heater Analysis with Artificial Ribs in V-Orientation

Abstract

The main drawback of the solar air heaters is their low convective heat transfer coefficient due to the creation of the laminar sublayer between the absorber plate and the air. This problem can be solved by creating artificial ribs on the absorber plate to break laminar sublayer. Artificial roughness will raise the pressure drop while also increasing the heat transfer coefficient, thus the ribs must be positioned so that they enhance the solar air heater's overall thermal-hydraulic performance. The study’s goals include analyzing the impact of NACA 0040 profile ribs in different V-orientations and optimizing the various V-orientational factors. In the present study, initially, experiments were carried out on the smooth plate at different Reynolds number ranging between 6000 to 18000 and the results were analyzed in term of Nusselt number and friction factor. The Nusselt number was found to be 12.13 to 46.28 and the friction factor was found to be 0.0040 to 0.0069. In the next phase, artificially roughened absorber plate was developed with NACA 0040 profile ribs in V-orientation with an attack angle of 105°. In the next semester, experiments were performed with this absorber plate.