Experimental investigation for pitch and angle of arc effect of discrete artificial roughness on Nusselt number and fluid flow characteristics of a solar air heater

Abstract

Artificial roughness element with gap used to enhance the performance of solar air heater. Compared to the traditional smooth absorber plate and absorber plate with artificial roughness element without gap, the thermo-hydraulic performance (THP) of discrete artificial roughened solar air heater was found more. An experimental study of the heat transfer and fluid flow properties of the solar air heater was carried out using artificial roughness with an area in the absorbent plate. At present, discrete rib roughness in a double reverse arc manner has been used with variations in mass flow from 3000 to 14000 in the form of Reynolds number. The range of roughness parameters, such as the first used for the constant value of α of 600 and p/e from 6.67, 8.33, 10, 11.67 and the second used for the fixed value p/e of 8.33 along with the arc angle change, α of 300, 450, 600, 750 in the properties of heat transfer and fluid flow to achieve. These experimental results are important for applying an improved solar air heater.