Automatic system for psychrometric calculations
DOI:
https://doi.org/10.13083/reveng.v28i.951Palavras-chave:
Data Acquisition, Physical properties of air, Computer softwareResumo
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.
Downloads
Referências
AGRAWAL, K.K.; RAO, H.V. A Computer Model of Psychrometric. Applied engineering in agriculture, p.67-73, 1974, doi:10.13031/2013.36789.
AOSONG. Temperature and humidity module - AM2302 product manual, 2018. Retrieved from http://img.filipeflop.com/files/download/Datasheet_DHT22_AM2302.pdf. Acessed in 20 Jun. 2018.
ASHRAH Dayton - American Society of Heating Refrigerating and Air-Conditioning Engineers. Psychrometric Properties SI Units, 2018. Retrieved from http://daytonashrae.org/psychrometrics/ psychrometrics_si.html. Acessed 15 Jun. 2018.
BELL, I.H.; LEMMON, E.W.; HARVEY, A.H. Algorithms for the calculation of psychrometric properties from multi-fluid Helmholtz-energy-explicit models. International Journal of Refrigeration, v.87, p.26-38, 2018, doi: 10.1016/j.ijrefrig.2017.10.001
BELTRÁN-PRIETO, J.C.; BELTRÁN-PRIETO, L.A.; NGUYEN, L.H.B.S. (2016). Estimation of psychrometric parameters of vapor water mixtures in air. Computer Applications in Engineering Education, v. 24(1), p.39-43, 2016, doi: 10.1002/cae.21670
COMPAGNON, A.M.; GAVA, R.; MARTINS, C.H. PSICRO 2009 – Computational program to determine the psychrometric properties of air (in Portuguese). Revista em Agronegócios e Meio Ambiente, v.3, p.251-269, 2009.
GUPTA, P.K.; PATEL, R.N.A teaching–learning tool for elementary psychrometric processes on psychrometric chart using MATLAB. Computer Applications in Engineering Education, v.25(3), p.458-467, 2017, doi:10.1002/cae.21813.
HJ ANDREWS EXPERIMENTAL FOREST. Dew point and vapor pressure deficit equations. Retrieved from https://andrewsforest.oregonstate.edu/sites/default/files/lter/data/studies/ms01/dewpt_vpd_calculations.pdf. Acessed 15 Aug. 2018.
JESUS, M.F.; SILVA, G.F. Software for estimating the psychrometric properties (in Portuguese). Revista Brasileira de Produtos Agroindustriais, v.4(79), p.63-70, 2002.
LOPES, R.P.; LOPES, D.C.; REZENDE, R.C. Basic Principles of Psychrometry (in Portuguese). In SILVA, J.S. (Ed.), Secagem e Armazenagem de Produtos Agrícolas. Viçosa, MG: Aprenda Fácil, 2008, p.37-62.
MARTÍN-GARÍN, A.; MILLÁN-GARCÍA, J.A.; BAÏRI, A.; MILLÁN-MEDEL, J.; SALA-LIZARRAGA, J.M. Environmental monitoring system based on an open source platform and the internet of things for a building energy retrofit. Automation in Construction, v.87, p.201-214, 2018, doi:10.1016/j.autcon.2017.12.017.
MELO, E.C.; LOPES, D.C.; CORRÊA, P.C. Grapsi - Computational program for the calculation of the psychrometric properties of air (in Portuguese). Revista Engenharia na Agricultura, v.12 (2), p.154-162, 2004.
MELO, E.C. The GRAPSI Computational Program (in Portuguese), 2011. Retrieved from http://evandromelo.com/artigos/Grapsi_tutorial.pdf. Accessed 07 Sep. 2019.
NOVA, N.V.; PEREIRA, A.B.; PEREIRA, A.R. Adjustments of S and W of the Penman equation as a function of the mean between the psychrometer temperatures (in Portuguese). IRRIGA (Brazilian Journal of Irrigation and Drainage), v.07(03), p.241-253, 2002, doi: 10.15809/irriga.2002v07n3p241-254.
PELLANDA, G.L. Graphic interface software for psychrometric chart (in Portuguese). V Semana de Engenharia Quimica UFES, 2006.
ROGDAKIS, E.D. An accurate and computationally efficient approximation to psychrometric calculations. International Journal of Latest Research in Science and Technology, v.3(3), p.2278-5299, 2014.
SCHIAVON, S.; HOYT, T.; PICCIOLI, A. (2014). Web application for thermal comfort visualization and calculation according to ASHRAE Standard 55. Building Simulation, v.7(4), p.321-334, 2014, doi:10.1007/s12273-013-0162-3.
SENAY, G.B. Satellite Psychrometric Formulation of the Operational Simplified Surface Energy Balance (SSEBop) Model for Quantifying and Mapping Evapotranspiration. Applied Engineering in Agriculture, v.34(3), p.555-566, 2018, doi:10.13031/aea.12614.
SINGH, A.K.; SINGH, H.S.; SINGH, S.P.; SAWHNEY, R.L. Numerical calculation of psychrometric properties on a calculator. Building and Environment, v.37(4), p.415-419, 2002, doi:10.1016/S0360-1323(01)00032-4.
WILHELM, L.R. Numerical calculation of psychrometric properties in SI units. Trans. ASABE, p.318-325, 1976, doi: 10.13031/2013.36019.
Downloads
Publicado
Como Citar
Edição
Seção
Licença
Copyright (c) 2020 REVISTA ENGENHARIA NA AGRICULTURA - REVENG
Este trabalho está licenciado sob uma licença Creative Commons Attribution-NonCommercial 4.0 International License.
Autores que publicam nesta revista concordam com os seguintes termos:
O(s) autor(es) autoriza(m) a publicação do texto na da revista;
O(s) autor(es) garantem que a contribuição é original e inédita e que não está em processo de avaliação em outra(s) revista(s);
A revista não se responsabiliza pelas opiniões, ideias e conceitos emitidos nos textos, por serem de inteira responsabilidade de seu(s) autor(es);
É reservado aos editores o direito de proceder a ajustes textuais e de adequação às normas da publicação.
A partir da submissão, o autor estará cedendo integralmente seus direitos patrimoniais da obra à publicação, permanecendo detentor de seus direitos morais (autoria e identificação na obra) e de acordo com a Licença Creative Commons, CC BY-NC.