Experimental assessment of the effect of reflectors on the thermal behavior of box-type solar furnaces

Abstract

Solar ovens are eco-friendly ovens that use solar energy, a clean, sustainable and above all free source of energy. In the context of the economic and environmental crises facing the world today, solar cookers are considered a good alternative to electric cookers or those based on wood combustion. Several types of solar cooker have been developed in recent years. However, the box type remains the most efficient and simplest. To this end, an experimental study of three types of box-type solar cookers (triangle, trapezoid and rectangle) was carried out in this work. For each type of solar cooker, the effect of the number of reflectors added to the Cookers system was examined. The experimental tests were carried out in August 2023 under the climatic conditions of Morocco's eastern region. The evaluation of the systems studied is based on the hourly evolution of air, absorber and load temperatures for each type of solar furnace in different cases. Thermal photos were also taken using a Dia-Cam thermal imaging camera to visualize temperature distribution and analyze the thermal behavior of the systems. The obtained results show that the thermal behavior of three solar furnaces and the evolution of the absorber temperature depend on the load used. In addition, a significant improvement in absorber temperature and water boiling time was observed with the addition of solar reflectors. For example, the absorber temperature was increased by up to 40 °C and the water boiling time was reduced by more than 120 min in the case of triangle-type furnaces.