The Drying Kinetics and CFD Multidomain Model of Cocoa Bean Variety CCN51

The CCN51 cocoa bean variety is known for being highly resistant to diseases and temperature variation and for having a relatively low cultivation risk for the producers. In this work, a computational and experimental study is performed to analyze the mass and heat transfer within the bean when dried by forced convection. A proximal composition analysis is conducted on the bean testa and cotyledon, and the distinct thermophysical properties are determined as a function of temperature for an interval between 40 and 70 degrees C. A multidomain CFD simulation, coupling a conjugate heat transfer with a semiconjugate mass transfer model, is proposed and compared to the experimental results based on the bean temperature and moisture transport. The numerical simulation predicts the drying behavior well and yields average relative errors of 3.5 and 5.2% for the bean core temperature and the moisture content versus the drying time, respectively. The moisture diffusion is found to be the dominant mechanism in the drying process. Moreover, a diffusion approximation model and given kinetic constants present a good prediction of the bean's drying behavior for constant temperature drying conditions between 40 and 70 degrees C.

Automated summary

In this study, a computational and experimental analysis of mass and heat transfer in the drying process of the CCN51 cocoa bean variety was performed. The study used a multidomain CFD simulation coupled with a conjugate heat transfer and semiconjugate mass transfer model. The results showed that moisture diffusion was the dominant mechanism in the drying process, and a diffusion approximation model with given kinetic constants provided a good prediction of the drying behavior.