Contribuição à modelagem da secagem em leito deslizante concorrente

• Ano de defesa: 2005
• Autor(a) principal: Lira, Taisa Shimosakai de
• Tipo de documento: Dissertação
• Tipo de acesso: Acesso aberto
• Idioma: por
• Instituição de defesa: Universidade Federal de Uberlândia; BR; Programa de Pós-graduação em Engenharia Química; Engenharias; UFU
• Palavras-chave em Português: Transferência de calor e massa; Sementes de soja; Leito deslizante; Perfil radial de velocidade; Análise de sensibilidade; Calor - Transmissão; Soja - Semente; Heat and mass transfer; Soybean seeds; Moving bed; Radial velocity profile; Sensitivity analysis; CNPQ::ENGENHARIAS::ENGENHARIA QUIMICA
• Link de acesso: https://repositorio.ufu.br/handle/123456789/15118

The modelling of heat and mass transfer between the air and soybean seeds in moving bed dryers is based on the application of mass and energy balances equations for both solid and fluid phases (two phases model). In the development of these equations, some classic hypotheses are assumed, such as flat air velocity profiles and constant physico-chemical parameter along the bed, among others. The main goal of this thesis was to discuss the validity of these assumptions in concurrent moving bed dryer modelling. For so much, several equations of bed porosity and air velocity distribution were considered and compared with experimental data. This study verified that non-flat fluid velocity profiles are significant in beds with reason dT /dp = 13, 3. The equation that best represented the experimental data was the Fahien e Stankovich (1979) equation. This equations was incorporated to the two phases model. Through comparisons between the experimental data and the simulated responses it was possible to verify the significant influence of the air velocity distribution in the drying process. The influences of some physico-chemical parameters of the model were also analyzed through sensitivity studies using experiment design and derivative methods using the code DASPK 3.0. The model presented large absolute sensitivity to the perturbations of the parameter specific heat of the dry air (Cpf ). This means then that small variations in the value of this parameter have strong influence in the results obtained by the model.