Natural and forced air convection operation in a direct solar dryer assisted by photovoltaic module for drying of green onion

Autor(es)

Hidalgo, Leticia Ferraresi ^[1] ; Candido, Mariana Nascimento ^[2] ; Nishioka, Karina ^[2] ; Freire, Jose Teixeira ^[1] ; Alves Vieira, Gustavo Nakamura ^[2]

Afiliação do(s) autor(es)

^[1] Fed Univ Sao Carlos UFSCar, Dept Chem Engn, Sao Carlos - Brazil

^[2] Sao Paulo State Univ, UNESP, Inst Chem, Dept Engn Phys & Math, Araraquara, SP - Brazil

• Tipo de documento: Artigo Científico
• Fonte: Solar Energy; v. 220, p. 24-34, MAY 15 2021.
• Citações Web of Science: 0

Resumo

The aim of this research was to develop a direct solar dryer assisted by photovoltaic module and evaluate its performance under natural and forced convection experiments. The photovoltaic module provides electrical power to eight coolers that allow the renewal of air inside the equipment. In this configuration, the dryer is capable of operating independently of electrical energy distribution grid. Moisture and colorimetric parameters were monitored during drying of green onion. Drying kinetics showed a constant rate period followed by a falling rate period for both operating conditions. The convection experiment showed a higher rate and external mechanisms may have controlled the process. Straight lines were adjusted to constants rate periods with R2 of 0.999. Page and Overhults models best described the falling rate periods, with R2 between 0.932 and 0.999. The effective diffusivity values were 5.15 x 10-9 m2/s and 1.15 x 10-8 m2/s for drying with natural and forced convection runs. The average efficiencies of the solar dryer and the specific energy consumption were 34.2%, 18.3 kWh/kg for the drying process with natural convection, and 38.3%, 16.4 kWh/kg for the drying process with forced convection. Little color variation was observed between fresh and dried green onions in the two operating conditions, which is consistent with the need to maintain the green color of the material. (AU)

• Processo FAPESP: 17/21890-5 - Monitoramento de variáveis de processo em secadores solares híbridos fotovoltaicos utilizando sensores virtuais: aplicação para secagem de alimentos
• Beneficiário: Gustavo Nakamura Alves Vieira
• Modalidade de apoio: Auxílio à Pesquisa - Regular
• Processo FAPESP: 18/24132-7 - Construção e instrumentação de um secador solar híbrido fotovoltaico para processamento de alimentos em pequena escala
• Beneficiário: Mariana Nascimento Candido
• Modalidade de apoio: Bolsas no Brasil - Iniciação Científica
• Processo FAPESP: 18/23762-7 - Avaliação de processo em secador solar híbrido fotovoltaico: aplicação para secagem de alimentos
• Beneficiário: Letícia Ferraresi Hidalgo
• Modalidade de apoio: Bolsas no Brasil - Mestrado
• Processo FAPESP: 19/17654-0 - Influência de condições operacionais de um secador solar híbrido fotovoltaico sobre parâmetros colorimétricos de produtos secos
• Beneficiário: Karina Nishioka
• Modalidade de apoio: Bolsas no Brasil - Iniciação Científica