Evaluation of some thin layer drying models and effective moisture diffusivity of yam (Dioscorea rotundata) slices.

B. K. Koua; P. M. E. Koffi; F. W. Fassinou; H. Y. Andoh; P. Gbaha; S. Touré

B. K. Koua Laboratoire d’Energie Solaire, UFR-SSMT- Université Félix Houphouet- Boigny de Cocody- Abidjan, 22 BP 582 Abidjan 22, (COTE D’IVOIRE)

P. M. E. Koffi Laboratoire d’Energie Nouvelle et Renouvelable, Département de Mécanique et Energétique- Institut National Polytechnique Félix Houphouet- Boigny de Yamoussoukro, B.P. 1526 Yamoussoukro

F. W. Fassinou Laboratoire d’Energie Solaire, UFR-SSMT- Université Félix Houphouet- Boigny de Cocody- Abidjan, 22 BP 582 Abidjan 22, (COTE D’IVOIRE)

H. Y. Andoh Laboratoire d’Energie Nouvelle et Renouvelable, Département de Mécanique et Energétique- Institut National Polytechnique Félix Houphouet- Boigny de Yamoussoukro, B.P. 1526 Yamoussoukro

P. Gbaha Laboratoire d’Energie Nouvelle et Renouvelable, Département de Mécanique et Energétique- Institut National Polytechnique Félix Houphouet- Boigny de Yamoussoukro, B.P. 1526 Yamoussoukro

S. Touré Laboratoire d’Energie Solaire, UFR-SSMT- Université Félix Houphouet- Boigny de Cocody- Abidjan, 22 BP 582 Abidjan 22, (COTE D’IVOIRE)

In this study, thin layer drying characteristics of yam were investigated experimentally in a convective dryer. The drying experiments were conducted at drying air temperatures of 35, 40 and 45°C and at an airflow rate of 0.60 m/s. seven thin layer drying models available in the literature were fitted to the experimental data. The fit quality of the proposed models was evaluated by using the determination of coefficient (r2), reduced chi-square (χ2), root mean square error (RMSE) and sum of residuals. The modified Page, Page and Weibull models showed a better fit to experimental drying data as compared to other models. The effective moisture diffusivity of the yam is found to increase with the drying air temperatures and ranged between 10.08x10-10 and 11.21x10-10 m2/s. Using the effective diffusivity and an Arrhenius type relationship, it is found that yam activation energy is 28.76kJ/mol.