Selection and Verification of a Drying Model for Maize (Zea mays L.) in Forced Convection Solar Grain Dryer

Booker Osodo^1, , Daudi Nyaanga² and Joseph Muguthu³

¹Department of Industrial and Energy Engineering, Egerton University, Nakuru, Kenya

²Department of Agricultural Engineering, Egerton University, Nakuru, Kenya

³Department of Energy Engineering, Kenyatta University, Nairobi, Kenya

Cite this paper:
Booker Osodo, Daudi Nyaanga and Joseph Muguthu. Selection and Verification of a Drying Model for Maize (Zea mays L.) in Forced Convection Solar Grain Dryer. American Journal of Food Science and Technology. 2017; 5(3):93-100. doi: 10.12691/ajfst-5-3-4

Abstract

Various researchers have fitted experimental drying curves for various products to existing drying models. In this study, an experimental forced convection solar grain dryer was used to select the best fitting drying model for shelled maize. 0.04 m thick grain layer of shelled maize was dried an air velocity of 0.408 m/s and a 40°C drying air temperature. Using Root Mean Square Error (RMSE), Coefficient of Determination (R²) and Chi Square (χ²) the selected drying model was the one by Midilli et al. (2002), with R², χ² and RMSE values of 0.9487, 0.4278 and 0.1723 respectively. The model coefficients were determined for drying air temperatures of 40, 45, 50 and 55°C. It was found that the predicted and experimental data agreed satisfactorily with R² and RMSE values of 0.9225-0.9786 and 0.0325-0.0750 respectively. A computer simulation model was developed to predict moisture ratio at a given drying time.

Keywords:
forced convection drying model model coefficients shelled maize computer simulation model

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