University of California

Dynamic modelling of a cross-flow rice dryer


David Platt
Tom R. Rumsey
Ahmet Palazoglu

Authors Affiliations

David Platt was on leave from RAFAEL, Israel; Tom R. Rumsey was Department of Agricultural Engineering, University of California, Davis; Ahmet Palazoglu was Department of Chemical Engineering, University of California, Davis.

Publication Information

Hilgardia 58(4):1-46. DOI:10.3733/hilg.v58n04p046. November 1990.

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A general dynamic model of a cross-flow dryer is developed from fundamental balance equations. Six dimensionless groups that govern the process are defined, and the resulting dimensionless equations are solved with the Method of Lines, using the Advanced Continuous Simulation Language (ACSL) software package. The mesh influence on the numerical solution is investigated. Stiffness analysis is performed for the system of partial differential equations, and the assumption of quasi-steady state for the air is discussed. Application of the model to rice-drying experiments shows good agreement. The results underline the potential of the model and the numerical solution strategy needed for critical physical insight into the operation of cross-flow rice dryers.

Literature Cited

Advanced Continuous Simulation Language (ACSL). Reference Manual. 1986. Concord, Mass.: Mitchell and Gauthier Associates.

American Society of Agricultural Engineers Standards. Equilibrium moisture content equations and constants 1988. p.319.

Bakker-Arkema F. W., Lerew L. E., Deboer S. F., Roth M. G. Grain Dryer Simulation 1974. Research Report 224. Mich. State Univ

Bakker-Arkema F. W., Fontana C., Schisler I. P. Comparison of rice drying systems 1983. Amer. Soc. Agr. Engin. Paper No. 83-3532. St. Joseph, Mich.: ASAE

Chandra P., Thompson J. F., Rumsey T. R., Singh R. P. Potential of air recycling in an industrial cross-flow rice dryer 1981. ASAE Paper No. 81-6514. St. Joseph, Mich.: ASAE

Davis M. E. Numerical methods and modeling for chemical engineers. 1984. New York, N.Y.: John Wiley &; Sons, Inc. p. 128-129.

Eltigani A. Y., Bakker-Arkema F. W. Automatic control of commercial cross-flow grain dryers. Drying Technology. 1987. 5(4):561-75. DOI: 10.1080/07373938708916563 [CrossRef]

Fontana C., Bakker-Arkema F. W., Westelaken C. M. Concurrent flow vs. cross-flow drying of long-grain rice. 1982. St. Joseph, Mich.: ASAE. ASAE Paper No. 82-3569

Gui X. Q., Bentsman J., Litchfield J. B. Control of grain drying: State of the art and open problems 1988. ASAE Paper No. 88-3502. St. Joseph, Mich.: ASAE

Holtman J. B., Zachariah G. L. Computer controls for grain dryers. Trans. Amer. Soc. Agr. Engin. 1969. 12(4):433-37.

Laws N., Parry J. L. Mathematical modelling of heat and mass transfer in agricultural grain drying. Proc. Roy. Soc. Lond. A. 1983. 385:169-87. DOI: 10.1098/rspa.1983.0009 [CrossRef]

Marchant J. A. Control of high temperature continuous flow grain dryers. The Agr. Engin. 1985. 40(4):145-49.

Otten L., Brown R., Anderson K. A study of commercial cross-flow grain dryer. Canadian Agr. Engin. 1980. 22(2):163-70.

Parry J. L. Mathematical modelling and computer simulation of heat and mass transfer in agricultural grain drying: A review. J. Agr. Engin. Res. 1985. 32:1-29. DOI: 10.1016/0021-8634(85)90116-7 [CrossRef]

Reid R. C., Prausnitz J. M., Poling B. E. The properties of gases and liquids 1987. p.212. 667, 669. New York, N.Y: McGraw-Hill Book Company

Rumsey T. R. Transient simulation of a cross-flow rice dryer 1986. Amer. Soc. Agr. Engin. Paper No. 86-6906. St. Joseph, Mich.: ASAE

Rumsey T. R. State equation model for a cross-flow dryer 1988. Amer. Soc. Agr. Engin. Paper No. 88-6070. St. Joseph, Mich.: ASAE

Schisler I. P., Bakker-Arkema F. W., Brook R. C. Control of concurrent flow grain dryers 1982. Amer. Soc. Agr. Engin. Paper No. 82-3613. St. Joseph, Mich.: ASAE

Thompson T. L., Peart R. M., Foster G. H. Mathematical simulation of corn drying—a new model. Trans. Amer. Soc. Agr. Engin. 1968. 11(4):582-86.

Wang C. Y., Singh R. P. A single layer drying equation for rough rice 1978. Amer. Soc. Agr. Engin. Paper No. 78-3001. St. Joseph, Mich.: ASAE

Wang C. Y., Rumsey T. R., Singh R. P. Convective heat transfer coefficient in a packed bed of rice 1979. Amer. Soc. Agr. Engin. and Canad. Soc. Agr. Engin. Paper No. 79-3040. St. Joseph, Mich.: ASAE

Whitfield R. D. An unsteady-state simulation to study the control of concurrent and counter-flow grain dryers. J. Agr. Engin. Res. 1986. 33:171-78. DOI: 10.1016/S0021-8634(86)80047-6 [CrossRef]

Zachariah G. L., Isaacs G. W. Simulating a moisture-control system for a continous-flow dryer. Trans. Amer. Soc. Agr. Engin. 1966. 9:297-302.

Platt D, Rumsey T, Palazoglu A. 1990. Dynamic modelling of a cross-flow rice dryer. Hilgardia 58(4):1-46. DOI:10.3733/hilg.v58n04p046
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