Energy performance study of a direct solar dryer installed under sub humid region

In this work a new approach for modeling the energy behavior of a direct solar dryer is developed. On the one hand, we used a detailed formulation to calculate accurately the various solar fluxes intercepted by dryer cover to develop a numerical model, and on the other hand, we considered the experimental results obtained using a solar dryer prototype, constructed and operated in the Solar Energy and Environment Laboratory and equipped with measuring instruments. We used hourly measurements of the global solar radiation incident on horizontal surface and the global solar radiation transmitted inside the dryer. Measurements were carried out in the city of Rabat in Morocco. The geometry effect of solar dryer on the daily intercepted solar energy profile was determined. Analysis of this effect allowed us to consider multiple geometric scenarios of the solar dryer, leading to choose an optimal structure able to receive and to transmit a maximum of daily solar energy, while the underlying performance calculation model not exceeding 6 % error in comparison with data measurements.