Performance Enhancement of a Single Pass Solar Air Heater by Adopting Wire Mesh Absorber Layer

Abstract

Solar air heaters are used for air heating, which is subsequently used for greenhouses warming and dry agricultural products. The performance of solar air heaters may be enhanced quite effectively adopting artificial surface geometry. In the current work, an absorber plate design with wire mesh layer in front pass typical solar air heater was examined and compared to a traditional flat absorber plate. Experimental investigation was conducted outside for three values of mass flow rates of 0.05 kg/s, 0.08 kg/s, and 0.11 kg/s. The average thermal efficiency is found to be 42.5%, 57.1% and 68.1% of the typical flat absorber plate, while it was 53.3%, 72.6% and 86.2% of flat absorber plate with wire mesh layer technology with the adopted values of flow rate. The newly proposed technique has much higher thermal efficiency than the traditional one. It encourages more uniform airflow through the absorber, augmentation the surface area and increase the rate of heat transfer, which is resulting in greater surface temperatures in the duct. The experimental study results show that the amount of solar radiation, mass flow rate and the geometry of the absorber surface are the main factors which are affecting on the performance of solar air heaters. The suggested absorber plate design, which features a wire mesh surface, might be utilized as an energy-efficient alternative to solar air warmers.