Author
PRAKASH, BHAGWATI - University Of California | |
Pan, Zhongli |
Submitted to: Proceedings of the American Society of Agricultural and Biological Engineers International (ASABE)
Publication Type: Proceedings Publication Acceptance Date: 6/21/2009 Publication Date: 6/21/2009 Citation: Prakash, B., Pan, Z. 2009. Heat and Mass Transfer Modeling of Rough Rice Under Convective and Infrared Drying. Proceedings of the American Society of Agricultural and Biological Engineers International (ASABE). ASABE Paper #096420. p. 1-16. St. Joseph, Mich. Interpretive Summary: This research studied the change in moisture gradient of rice kernels during drying by using a mathematical modeling method. It provided knowledge in drying mechanism for improved rice milling quality. Technical Abstract: Infrared drying of rice can reduce drying time, perform disinfestations and reduce rice fissuring compared to traditional hot air drying method. Fissures in the rice kernels are caused by high moisture content gradients within the kernels. To understand the moisture distributions within a rice kernel under different drying methods, we have developed a coupled heat and mass transfer processes-based model. In this model, the rough rice kernel is considered to be three-dimensional ellipsoid composed of three components: hull, bran and endosperm. The model is solved by finite element method using COMSOL Multiphysics simulation tool. The model is validated by experiments conducted using a laboratory scale infrared dryer and a convective air column dryer. For these experiments, Californian medium grain ice variety, M206, with three different initial moisture contents, were used. Model predictions show a good agreement with the experimental results. Using this model, a multi-pass drying process can be designed to minimize the moisture gradients, reduce the fissures and thus improve the crop market value. |