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Drying of Grains in Conveyor Dryer and Cross Flow: A Numerical Solution Using Finite-Volume Method

DOI: http://dx.doi.org/10.15871/1517-8595/rbpa.v6n1p1-16

http://rbpaonline.com/ 

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Raimundo P. de Farias1, Deivton C. Santiago2, Pedro R. H. de Holanda3 & Antonio G. B. de Lima4

 

Abstract: The drying of solids in cross flow band conveyor dryer (continuous operation system) in which particles (thin-layer) move in a wire net conveyor was theoretically studied. A mathematical modeling that considers the influence of the bed porosity and the transient terms in the drying process was developed. The finite volume method and upwind formulation to convective terms were used to solve numerically the governing conservation equations. The results of the relative humidity and temperature of the air and temperature and moisture content of the material (yellow corn kernel) along the drying process are presented and analyzed to examine the influence of the main drying parameters on the quality of the product in the end of the process. This study can be used to help researchers in the optimization of this and others types of driers under small modifications.

Key words: drying, finite-volumes, dryer, net conveyor, corn.

 

Resumo: Este trabalho tem como objetivo, estudar a secagem de sólidos em secador de esteira e fluxos cruzados (sistema de operação contínua) em que partículas (em camada fina) movem-se em uma esteira transportadora. O modelo proposto considera a influencia da porosidade do leito e os termos transientes no processo de secagem. As equações que descrevem o problema físico foram resolvidas numericamente utilizando o método numérico dos volumes finitos considerando o esquema upwind como função de interpolação para os termos convectivos. Para verificar a influencia dos principais parâmetros de secagem na qualidade do produto no final do processo, resultados da temperatura e umidade relativa do ar de secagem, e do teor de umidade e temperatura do grão de milho durante o processo de secagem são mostrados e analisados. Esta pesquisa pode ser usada para ajudar pesquisadores na otimização deste e de outros tipos de secadores realizando poucas modificações no modelo.

Palavras-chave: secagem, volumes finitos, secador, esteira transportadora, milho.

 

1 Mestre em Engenharia Mecânica, Departamento de Engenharia Mecânica, CCT, Universidade Federal de Campina Grande (UFCG), CEP 58109-970, Cx. Postal 10069, Campina Grande-PB, Brasil. Fone (083) 310-1317
2 Graduando em Engenharia Mecânica, Departamento de Engenharia Mecânica, CCT, Universidade Federal de Campina Grande (UFCG), Campina Grande-PB, Brasil. Bolsista PIBIC/UFPB/CNPq.
3 Doutorando em Engenharia de Processos, CCT, Universidade Federal de Campina Grande, Campina Grande-PB, Brasil.
4 Professor Doutor do Departamento de Engenharia Mecânica, CCT, Universidade Federal de Campina Grande (UFCG), CEP 58109-970, Cx. Postal 10069, Campina Grande-PB, Brasil. Fone (083) 310-1317, e-mail: gilson@dem.ufcg.edu.br

  

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