Thermal Performance of Solar Air Heater Having Triangular-Shaped Hollow Bodies Inside

Today, solar energy has emerged as an alternate to the conventional source of energy. Solar air heater (SAH) is one of the significant devices to convert solar energy into heat energy of fluid. Lower efficiency of SAHs is one of the major drawbacks. Hence, researcher in the recent past tried to increase efficiency of SAHs by putting different shapes and arrangement of roughness and baffles on the absorber plate. In this work, triangular-shaped hollow bodies are putted inside the solar air heater to improve its efficiency. Turbulence is produced locally due to existence of these bodies. Here, these bodies will act as fins also. This results in increase of heat transfer area and heat transfer coefficient between absorber and air. Loss of pressure is also less. Maximum enhancement obtained in efficiency is 8.34% for the mass flow rate at 0.012 kg/s. Maximum rise in temperature for Case-I (without triangular bodies) was recorded as 10.2 °C, whereas for Case-II (with triangular bodies) 13.1 °C achieved. CFD simulation results and experimental results obtained have good agreement.