Effect of inserting 10-PPI copper foam as a porous absorber on the solar cooker performance

Sustainable development is confronted with various challenges, and one of them is the scarcity of energy. To meet the needs of present and future generations, investments, technologies, and institutions need to evolve. One promising solution is the utilization of solar cookers. These cookers operate without the need for fuel or coal, resulting in cost and time savings. In the present study, two box-shaped solar cooker models were tested under identical conditions to assess their thermal performance and identify areas for improvement. The first model employed a copper absorber plate, while the second model utilized copper foam sheets with a porosity of 10 pores per inch (PPI). The experimental testing took place in Baghdad City, Iraq, in September 2022. The cookers were positioned towards the south at a latitude of 33.3° N and a longitude of 44.4° E. During the experimental testing, the copper foam with 10-PPI was used as the heat absorber plate, and various inclination angles (0°, 3°, 6°, and 9°) were examined. The results demonstrated that the solar cooker with a 10 PPI copper foam absorber achieved a stagnation temperature approximately 25.8 degrees higher than a standard absorber of the box-shaped solar cooker. Furthermore, using a 10-PPI copper-foam absorber plate reduced the cooking period in the box-shaped solar oven by up to 33% compared to a flat conventional absorber plate. The mean temperatures of the 10-PPI copper-foam absorber plate increased as the inclination angle rose, reaching its optimal internal air temperature at an inclination of 6 degrees. The equation of the cooking power provided a reliable indication that the cooker consistently cooked food and boiled water within an acceptable range.