Thermal performance evaluation of an indirect solar dryer

Thermal performance evaluation of an indirect solar dryer

Koua Kamenan BlaiseKoffi Ekoun Paul Magloire Gbaha Prosper 

Laboratoire d’Energies nouvelles et Renouvelables, UMRI 58, Institut National Polytechnique Félix Houphouët Boigny, B.P. 581 Yamoussoukro, Cote d’Ivoire

Laboratoire d’Energie Solaire, UFR SSMT, Université Félix Houphouët Boigny, 22 B.P. 582 Abidjan 22, Cote d’Ivoire

Corresponding Author Email:
31 March 2018
| Citation



The thermal performance of an indirect forced convection solar dryer was investigated experimentally with cocoa beans as drying products. The dryer mainly consists of a solar collector, a drying chamber and two fans. Two photovoltaic panels and battery storage are also integrated with the dryer to supply the required electrical energy. Experiments were performed for three different meteorological conditions. The results show a temperature for air inside the solar collector rise of 22.1 °C, 15.6 °C and 13.2 °C with respect to the ambient air temperature, for the sunny day, partially covered day and cloudy day, respectively. The average solar flux on the collector was 644 W/m2, 448 W/m2 and 341 W/m2, for the sunny day, partially covered day and cloudy day, respectively. The thermal efficiency of the solar collector varied between 34.89 % and 43.40 % whatever the type of day. The thermal drying efficiency of the indirect solar dryer varied between 14.48 % and 20.17 %. The hourly variation of drying chamber temperature is much higher than the ambient air temperature during the experiments.


indirect solar dryer, thermal efficiency, temperature, solar radiation

1. Introduction
2. Materials and methods
3. Results and discussion
4. Conclusion

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