Computational fluid dynamic model analysis of multipurpose dryer with bio-waste heat source: An experimental validation using paddy rice

Abstract

The quest to develop an appropriate drying technology that is sustainable while minimizing energy losses was the key motivation of this work. In this study, COMSOL multiphysics CFD software was used to model and simulate computational behaviour of a fabricated multipurpose crop dryer equipped with a bio-waste heat source. The generated thermal flow was deployed for drying of paddy rice given the rice drying characteristics. Meanwhile, the drying chamber was finitely discretized into little fragments in order to obtain a better distribution, result and efficiency. The temperature, pressure, and velocity distribution were analysed with simulated optimal drying temperature of paddy rice as 43 °C. This was attained for both simulated and experimented. It was observed that there was higher pressure and velocity at the fan orifice but a decrease as the air moves up the chimney surface as the drying chamber’s average temperature variation required for drying paddy rice was established, with relative error of 0.019 %. The simulated and experimental mean drying chamber efficiency were 90.3 % and 89 % respectively. Therefore, the fabricated multipurpose dryer is a good system for grain drying.

Keywords

• Crop dryer
• Model simulation
• Computational fluid dynamics
• Bio-waste burner