TITLE:
A Modeling Study for Moisture Diffusivities and Moisture Transfer Coefficients in Drying of “Violet de Galmi” Onion Drying
AUTHORS:
Aboubakar Compaoré, Samuel Ouoba, Kondia Honoré Ouoba, Merlin Simo-Tagne, Yann Rogaume, Clément Ahouannou, Alfa Oumar Dissa, Antoine Béré, Jean Koulidiati
KEYWORDS:
“Violet de Galmi” Onion, Diffusion Coefficient, Drying Coefficient, Lag Factor
JOURNAL NAME:
Advances in Chemical Engineering and Science,
Vol.12 No.3,
July
28,
2022
ABSTRACT: In the present work, the mass transfer
characteristics, namely moisture diffusivity and moisture transfer coefficient
of “Violet de Galmi” variety of
onions were evaluated using the analytical model. Onions were dried in a single
layer at different temperatures (40℃, 50℃, 60℃, and 70℃) and for a relative
humidity of drying air of 20%. The results showed a reasonably good agreement
between the values predicted by the correlation and the experimental
observations. This model computed the Biot number, effective moisture diffusivity, and mass transfer coefficient. Effective
diffusion coefficient values are obtained between 0.2578 × 10-9 m2·s-1 and
0.5460 × 10-9 m2·s-1. Mass transfer coefficients
of “Violet de Galmi” onion drying vary
between 3.37 × 10-7 m·s-1 and 13.38 × 10-7 m·s-1. Numbers of mass transfer Biot are found between 0.9797 and
2.9397. The activation energy Ea is 31.73 kJ·mol-1.