Dimensionless variable groups for the free-fall grain dryer
DOI:
https://doi.org/10.25165/ijabe.v12i4.4188Keywords:
dimensionless variable, similarity, free-fall dryer, rough riceAbstract
Dimensionless variable groups (DGs) of free-fall grain dryer were developed by using the characteristic scaling method and engineering intuition. These DGs were intended for the analyses of drying characteristics and sizes of this dryer. Experiments of the free-fall rough rice dryer were carried out using different drying chambers (small and medium scales), drying air temperatures (100°C-150°C), and drying air speeds (1-3 m/s). Experimental data were used to study relationships and to validate similarities among these DGs. The results of the study showed the five appropriate dimensionless variables representing and describing the drying mechanism of the free-fall dryer. These DGs could be applied to design and analyze scaling up the dryer. In addition, the dimensionless correlation was established to predict the moisture contents of rough rice while being dried by the free-fall dryer. The predicted values from this correlation were in relatively good agreement with the experimental data under the proposed drying conditions (R2=0.989, MRD=1.82% and RMSE=0.0168). Keywords: dimensionless variable, similarity, free-fall dryer, rough rice DOI: 10.25165/j.ijabe.20191204.4188 Citation: Meesukchaosumran S, Chitsomboon T. Dimensionless variable groups for the free-fall grain dryer. Int J Agric & Biol Eng, 2019; 12(4): 197–204.References
Chitsomboon T, Rung K. Dimensionless variables in drying process. In Proceedings of the 12th Conference of National Mechanical Engineering Network of Thailand, Bangkok, Thailand, 1998.
Koonsrisuk A, Chitsomboon T. Dynamic similarity in solar chimney modelling. Solar Energy, 2007; 81: 1439–1446.
Hall C W. Dimensionless numbers and groups for drying. Drying Technology, 1992; 10: 1081–1095.
Pavon-Melendez G, Hernandez J A, Salgado M A, Garcia M A. Dimensionless analysis of the simultaneous heat and mass transfer in food drying. Journal of Food Engineering, 2002; 51: 347–353.
Topuz A, Hamzacebi C. Moisture ratio prediction in drying process of agricultural products: A new correlation model. Applied engineering in agriculture, 2010; 26(6): 1005–1011.
Inaba H, Husain S, Horibe A, Haruki N. Heat and mass transfer analysis of fluidized bed grain drying. Memoirs of the Faculty of Engineering, Okayama University, 2007; 41: 52–62.
Kachru R P, Matthes R K. Kinetics of batch drying of deep-bed rough rice using dimensional analysis. Cereal Chemistry, 1976; 53: 61–71.
Zare D, Jayas D S, Singh C B. A generalized dimensionless model for deep bed drying of paddy. Drying Technology, 2012; 30: 44–51.
Zheng X, Yubin L, Wang J, Dong H, Process analysis for an alfalfa rotary dryer using an improved dimensional analysis method. International Journal of Agricultural and Biological Engineering, 2009; 2(3): 76–82.
Chitsomboon T, Khaengkarn S, Pechnumkheaw K. Free-fall-paddy rice dryer: A fast and energy efficient dryer. In Proceedings of the 2nd Conference on Energy Technology Network of Thailand, Nakhon Ratchasima, Thailand, July 27-29, 2006.
Meesukchaosumran S, Chitsomboon T. Effects of resting periods, air temperatures and air velocities on free-fall paddy dryer performances. Suranaree Journal of Science and Technology, 2018; 25(1): 11–26.
Khaengkarn S, Meesukchaosumran S, Chitsomboon T. Genetic algorithm for the selection of rough rice drying model for the free-fall paddy dryer. International Journal of Research and Applications in Mechanical Engineering, 2010; 1: 63–75.
Sarker M S H, Ibrahim M N, Ab Aziz N, Mohd Salleh P. Energy and rice quality aspects during drying of freshly harvested paddy with industrial inclined bed dryer. Energy Conversion and Management, 2014; 77: 389–395.
Prachayawarakorn S, Tia W, Poopaiboon K, Soponronnarit S. Comparison of performances of pulsed and conventional fluidised-bed dryers. Journal of Stored Products Research, 2005; 41: 479–497.
Sarker M S H, Ibrahim M N, Ab Aziz N, Mohd Salleh P. Energy and exergy analysis of industrial fluidized bed drying of paddy. Energy, 2015; 84: 131–138.
Brooker D B, Bakker-Arkema F W, Hall C W. Drying and storage of grains and oilseeds. New York: Van Nostrand Reinhold, 1992; 3p.
Soponronnarit S. Drying grain and some food. Bangkok: King Mongkut’s University of Technology Thonburi, 1997; 75p.
Elbert G, Tolaba M P, Aguerre R J, Suarez C. A diffusion model with a moisture dependent diffusion coefficient for parboiled rice. Drying Technology, 2001; 19: 155–166.
Teffe J F, Singh R P. Diffusion coefficient for predicting rice drying behavior. Journal of Agricultural Engineering Research, 1982; 27: 489–493.
Chitsomboon T. Fluid mechanics. Bangkok: McGraw-Hill/Top, 2003; pp.176–189.
Poomsa-ad N, Soponronnarit S, Prachayawarakorn S, Terdyothin A. Effect of tempering on subsequent drying of paddy using fluidization technique. Drying Technology, 2002; 20(1): 195–210.
Downloads
Published
How to Cite
Issue
Section
License
IJABE is an international peer reviewed open access journal, adopting Creative Commons Copyright Notices as follows.
Authors who publish with this journal agree to the following terms:
- Authors retain copyright and grant the journal right of first publication with the work simultaneously licensed under a Creative Commons Attribution License that allows others to share the work with an acknowledgement of the work's authorship and initial publication in this journal.
- Authors are able to enter into separate, additional contractual arrangements for the non-exclusive distribution of the journal's published version of the work (e.g., post it to an institutional repository or publish it in a book), with an acknowledgement of its initial publication in this journal.
- Authors are permitted and encouraged to post their work online (e.g., in institutional repositories or on their website) prior to and during the submission process, as it can lead to productive exchanges, as well as earlier and greater citation of published work (See The Effect of Open Access).
