Modeling and Experimental Validation of Solar Drying of Maize in a Greenhouse-type Dryer under Tropical Climate

Kokou GNRONFOU^{1, 2}, Tchamye Tcha-Esso BOROZE^{1, 3,} and Essohouna TAKOUGNADI^{1, 2}

¹Department of Physics, University of Lomé, 01 B.P. 1515 Lomé, Togo

²Research Team on Agricultural Mechanization and Process Engineering (ERMAP), University of Lomé, 01 B.P. 1515 Lomé, Togo

³Regional Center of Excellence for Electricity Management (CERME), University of Lomé, 01 B.P. 1515 Lomé, Togo;Research Team on Agricultural Mechanization and Process Engineering (ERMAP), University of Lomé, 01 B.P. 1515 Lomé, Togo

Cite this paper:
Kokou GNRONFOU, Tchamye Tcha-Esso BOROZE and Essohouna TAKOUGNADI. Modeling and Experimental Validation of Solar Drying of Maize in a Greenhouse-type Dryer under Tropical Climate. American Journal of Food Science and Technology. 2025; 13(6):156-163. doi: 10.12691/ajfst-13-6-2

Abstract

Solar drying is a sustainable post-harvest technique for maize valorization in tropical regions, but its performance strongly depends on thermal stability and solar radiation variability. This study presents the modeling and experimental validation of a solar greenhouse dryer, developed using coupled heat and mass balance equations expressed in matrix form. Simulations were compared with experimental data obtained from an instrumented prototype during three consecutive drying days. A strong agreement was found between simulated and measured values (MAE < 5°C; R² > 0.98). Internal air temperatures (45-57°C) ensured uniform evaporation, reaching a hygroscopic equilibrium moisture content of 10% within two days. The average thermal efficiency was 8.81%, indicating effective solar energy utilization. The obtained results confirm the relevance of solar-biomass coupling in stabilizing the drying process, improving energy efficiency, and maintaining the quality of dried maize under tropical climates.

Keywords:
solar drying maize greenhouse dryer thermal performance energy efficiency tropical climate

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