Thermal Analysis of New Solar Air Heater with Inclined Perforated Absorber Plates: Experimental Study

Solar air heaters (SAHs) have an inherent drawback: the conventional mechanism is low inside these collectors’ types. Use of perforations is a simple technique to improve convection, and this investigation experimentally assesses a novel design SAH utilizing three inclined perforated absorber plates. Two scenarios are considered to assess the dynamics and efficiency of this perforated SAH, including mair = ۰.۰۱۲ kg/s and ۰.۰۲۴ kg/s. Numerous sensors monitored the dynamics of the perforated SAH and ambient factors for ۱۲ hours in October ۲۰۲۲. The experimental outcomes illustrate that the perforation method remarkably enhances the thermal efficiency of the perforated SAH compared with standard smooth SAHs. The daily thermal efficiency of the perforated SAH reaches ۷۳.۳۰% and ۸۲.۶۵%, while the outlet air temperature experiences peak values of ۳۹ oC and ۴۲ oC at noon and keeps within ۹۰% of its maximum value for ۲ hours for the scenarios considered. Improving the convection mechanism causes the flowing air to extract the absorber’s thermal energy more effectively. Hence the SAH can produce an airstream near its maximum temperature for an extended duration. In conclusion, the perforation method is a robust, simple method to boost the thermal efficiency of SAHs.

Keywords:

Perforation method , Perforated solar air heaters , Thermal efficiency , Transient heat dynamics