Predictability of the Two Commonly Used Models to Represent the Thin-layer Re-wetting Characteristics of Barley

Authors: M. A. Basunia

Abstract:

Thirty three re-wetting tests were conducted at different combinations of temperatures (5.7- 46.30C) and relative humidites (48.2-88.6%) with barley. Two most commonly used thinlayer drying and rewetting models i.e. Page and Diffusion were compared for their ability to the fit the experimental re-wetting data based on the standard error of estimate (SEE) of the measured and simulated moisture contents. The comparison shows both the Page and Diffusion models fit the re-wetting experimental data of barley well. The average SEE values for the Page and Diffusion models were 0.176 % d.b. and 0.199 % d.b., respectively. The Page and Diffusion models were found to be most suitable equations, to describe the thin-layer re-wetting characteristics of barley over a typically five day re-wetting. These two models can be used for the simulation of deep-bed re-wetting of barley occurring during ventilated storage and deep bed drying.

Keywords: Thin-layer, barley, re-wetting parameters, temperature, relative humidity.

Digital Object Identifier (DOI): doi.org/10.5281/zenodo.1056577

References:

[1] O. R. Kunze, and S. Prasad, " Grain fissuring potentials in harvesting and drying rice" Transactions of the American Society of Agricultural Engineering 21(2), 361-266, 1978.
[2] M. A. Basunia and T. Abe. "Thin-layer moisture adsorption studies of barley" Transactions of the American Society of Agricultural Engineering 46(1), 125-131, 2003.
[3] M. A. Basunia, and T. Abe, "Adsorption isotherms of barely at low and high temperatures" Journal of Food Engineering 66(1), 129-136, 2005a.
[4] M. A. Basunia and T. Abe, "Thin-layer re-wetting of rough rice at low and high temperature" Journal of Stored Products Research 41, 163- 173, 2005b.
[5] J. S. Digvir and S. Sokhansanj, "Thin-layer drying of wheat at low temperatures" In Drying: (Mujumdar A S ed.), Hemisphere Pub. Corp., New York, NY. 844-847, 1986.
[6] J. S. Digvir and S. Sokhansanj,"Thin-layer drying of barley at low temperatures" Canadian Agricultural Engineering 31, 21-23, 1988.
[7] M. K. Misra, and D. B. Brooker, "Thin-layer drying and re-wetting equations for shelled yellow corn" Transactions of the American Society of Agricultural Engineering, 1254-1260. 1980.
[8] S. Sokhansanj, J. S. Digvir, and J. D. Wasserman, J.D. " Drying characteristics of wheat, barley and canola subjected to repetitive wetting and drying cycles" Transactions of the American Society of Agricultural Engineering, 27(3), 903-914, 1984.
[9] A. B. Newman, "The drying of porous solid. Diffusion and surface emission equation" Transaction of the American Institute of Chemical Engineering 27, 310-333, 1931.
[10] C. Page, "Factors influencing the maximum rate of drying shelled corn in layers" M. S. Thesis, Purdue University, W. Lafayette, IN, USA, 1949.