EXERGETIC ANALYSIS OF THE SOYBEAN DRYING PROCESS WITH SOLAR ENERGY IN HOT-HUMID CLIMATES

Abstract

Recently, solar dryers research has focused on determining the drying kinetics and its description from mathematical models; however, exergetic studies are relatively limited. Theoretical and experimental studies are required to break the knowledge barrier with this approach, assessing the maximum potential useful work wasted (exergy loss) by a system as it equilibrates with a reference environment (environment). Through the instrumentation of cabinet–type solar dryers, this work presents the exergetic analysis to evaluate the heat and mass transfer processes of soybean in hot-humid climates. The thermal performance of solar dryer with natural and forced convection was compared. The behavior of irradiance, ambient temperature, and relative humidity and their relationship with weight loss were analyzed. For natural and forced convection, the average exergetic efficiencies were 47.40% and 53.67%, respectively. Sustainability indicators were estimated: improvement potential, sustainability index, and wasted energy ratio. The exergetic performance was better in the process with forced convection compared to natural Keywords: Exergetic analysis, Solar drying technologies, Sustainability indicators.