Automatic system for psychrometric calculations




Data Acquisition, Physical properties of air, Computer software


Air psychrometric properties are important in several areas of agricultural engineering, such as calculation of evaluation of the animal environment and air control in grain storage units. Due to their relevance and the complexity and the uncertainties in the use of psychrometric charts, the objective of this paper was to develop the software, PsyCalculator, which stands out for the automated function that allows presenting the data acquired through sensors and the respective psychrometric properties of the air, either in graph or tables. The automatic data acquisition system consists of a microcontroller that performs readings of sensors that measure the dry bulb temperature and another variable, which may be: wet bulb temperature, relative air humidity or dew point temperature. Then, the values are sent to the PsyCalculator software system. In addition to the values ??of dry bulb temperature, the software system presents wet bulb temperature and dew point temperature, values ??of saturation vapor pressure, vapor pressure, mixing ratio, specific volume, enthalpy and degree of saturation. Among the psychometric variables analyzed, the software developed in the study presented a maximum error of 2.14% for the calculation of dew point temperature. The developed software allows the automation of systems that depend on the psychrometric parameters in a friendly and precise fashion.


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Biografia do Autor

Larissa Carolina Corraide da Silva, Universidade Federal de Viçosa

Mestranda em Engenharia Agrícola Departamento de Engenharia Agrícola Área de energia na agricultura

Delly Oliveira Filho, Universidade Federal de Viçosa

Professor no departamento de Engenharia Agrícola Área de energia na agricultura

Arthur Caio Vargas e Pinto, Universidade Federal de Viçosa

Mestre em Engenharia Agrícola Departamento de Engenharia Agrícola Área de energia na agricultura

Matheus Lima Diniz Araujo, University of Minnesota

Doutorando em Ciências da Computação Departamento de Ciências da Computação


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Como Citar

Corraide da Silva, L. C., Oliveira Filho, D., Vargas e Pinto, A. C., & Diniz Araujo, M. L. (2020). Automatic system for psychrometric calculations. Revista Engenharia Na Agricultura - REVENG, 28(Contínua), 129–139.



Armazenamento e Processamento de Produtos Agrícolas