Computational Fluid Dynamics Analysis in a Corn Air Flow Paddy Dryer with Two Types of Passing Air Flow of Lateral and Central Pattern

Document Type : Research Paper


1 Department of Agricultural Engineering Research, Fars Research and Education Center for Agriculture and Natural Resources, Agricultural Research, Education and Extension Organization (AREEO), Shiraz, P.O. Box:71555-617, Iran

2 Graduated Student, Engineering College, Bafgh Branch, Islamic Azad University, Bafgh, Iran

3 Agricultural Engineering Research Institute, Agricultural Research, Education and Extension Organization (AREEO), Karaj, Iran


Drying process is not uniform in the common rice dryers (batch type dryers). In order to decrease this problem, two types of passing hot air dryer consisted of the lateral and central patterns has been defined and method of air distribution in the rice porous media modeled by Fluent software in transient condition. In the lateral pattern, air enters through the side walls of the dryer chamber and in the central pattern, air enters through the central channel of the dryer chamber. The air temperature is 40 oc and air flow rate is 550 m3/h in all models. The results of simulation illustrate, the air flows more rapidly in the central pattern and penetrates into all parts of the dryer chamber. There is not any central passing air channel in the lateral pattern so, it caused to produce an irregular temperature field with high distortion. Models were verified in steady state condition. Results show the final temperature of model was near the measured data with 2% deviation.


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