Simulation Of Indirect Solar Crop Dryers Augmented With Pebble-Bed Thrmal Storages
Keywords:
Air collector applications , Indirect solar dryers, Rice and tomatoes preservation , Natural hot air flow , Natural buoyancy forcesAbstract
This paper presents a model of indirect solar dryer augmented with pebble bed thermal storage. The thermal storage system was considered to be placed inside the drying chamber above the 47°-tilted air solar collector and below the crop bed, where an average September-daily insolation profile was given for the 32°N location. A presented mathematical model took into consideration the pressure and natural buoyancy forces, employed the basic governing equations, atmospheric-air psychometric-chart relations, and published correlation relationships. A “QBASIC” computer program was written based on the trial and error method for the calculation of different parameters. Dimensions of the dryer system, position, and characteristics of the crop and storage beds, strongly affected the behavior of the dryer system, for both rice and tomato products. Referring to the considered indirect solar dryer design type, on average two and five days were required for rice and tomatoes long-term drying, respectively. This seems to be visible in rice products, however, it is far from applicability for tomatoes mass-drying process in agricultural fields, due to its high initial moisture content.
Downloads
Metrics
References
. Liberty, J. T., Okonkwo, W. I., and Ngabea, S. A., Solar Crop Drying-A Viable Tool For Agricultural Sustainability And Food Security, International Journal Of Modern Engineering Research, Vol. 4. Iss. 6, June 2014.
. Balakrishnan, A. R. and Pei, D. C. T., Heat Transfer in Fixed Beds, Ind. Eng. chem., Process Design and Develop., 13, 441-446, 1974.
. Oosthuizen, P. H., Modelling of an Indirect Natural Convective Solar Rice Dryer, Proceeding of the Ninth Symposium on Engineering Applications of Mechanics, 434-441, May 1988.
. Schubert, R. C., and Ryan, L. D., Fundamentals of Solar Heating, Prentice-Hall, Inc., New Jersey, 1981.
. Khama, R., Aissani, F., and Alkama, R., Design And Performance Testing Of An Industrial-Scale Indirect
Solar Dryer, Journal of Engineering Science and Technology, Vol. 11, No. 9, 1263 – 1281, 2016.
. El-Sebaii, A. and Shalaby, S.M., Solar Drying Of Agricultural Products: A Review. Renewable And Sustainable Energy Reviews 16.37-43, 2012.
. Gross, R. J., Hickox, C. E. and Hackett, C. E., Numerical Simulation of Dual Media Thermal Energy Storage
Systems, Journal of Solar Energy Engineering, ASME Trans, 102, 287-293 (1980).
. Oosthuizen, P. H., Design of Natural Convective Solar Crop Dryers for Use in West Africa, Proceeding of the
th Solar Energy Society of Canada, Penticton, B. C., 1989.
. Sansaniwal, S. K. and Kumar, M., Analysis of ginger drying inside a natural convection indirect solar dryer: An experimental study. Journal of Mechanical Engineering and Sciences; Volume 9, pp. 1671-1685, December 2015.
. Sheriff A. Y., An Experimental Study of A Simulated Natural Convection Solar Rice Dryer, M.Sc. thesis,
Queen’s University at Kingston, 1987.
. Preston, E. G. A., Simulation of A Natural Convection Solar Rice Dryer, M.Sc. thesis, Queen’s University at
Kingston, 1985.
. Elbenghazi, E. M., Modeling The Thermal Behavior Of Indirect Solar Dryers Augmented with Pebble-Bed
Thermal Storage, M. Sc. Thesis, University of Tripoli, Tripoli, Libya, 2013.
. Bejan, A., Convection Heat Transfer, John Wiley & Sons, New York, 1984.
. Excell, R. H. B., Basic Design Theory for A Simple Solar Rice Dryer, Renewable Energy Review Journal, 1, 2,
, 1980.
. Chavda, T. V., Agravat, S. M. and Philip, S. K., Drying of Tomato Using A Solar Dryer Incorporated with A
LPG Back up, ISAE, 42nd Annual convection held at CIAE, Bhopal, 474 – 496, 2008.
. Duffi J. A., and Beckman, W. A., Solar Engineering of Thermal Processes, John Wiley & Sons, New York,
. Oosthuizen, P. H., A Numerical Study of The Performance of Natural Convection Solar Rice Dryers, Proceedings of the 5th International Symposium on Drying, Drying ‘86, Vol. 2, 670 -677, Boston, Massachusetts, August 13 - 15, 1986.
. Sayigh, A. A. M., Th Technology of Flat Plate Collectors in Solar Energy Conversion-An Introductory Course,
eds. A. E. Dixon and J. D. Leslie, 101-124, Pergamon Press, Toronto, 1969.
. Local Solar Insolation Data Report, Mean Monthly Solar Radiation Measurements, Information Department, Center For Solar Energy Studies, Tripoli, Libya, 1985.
. Bassey, M. W., Influence of Chimney Configuration on Temperatures in A Solar Crop Dryer, Proceedings
of Energex ‘82 Conference, Vo1.11/11, P. 862, August 23-29, University of Regina, Regina, Saskatchewan,
Canada, 1982.
