@TechReport{SilvaJrCost:2021:DePrEq,
               author = "Silva Junior, Jos{\'e} Raimundo da and Costa, Fernando de Souza",
                title = "Desenvolvimento de programa de equil{\'{\i}}brio 
                         qu{\'{\i}}mico para aplica{\c{c}}{\~o}es em combust{\~a}o e 
                         propuls{\~a}o",
          institution = "Instituto Nacional de Pesquisas Espaciais",
                 year = "2021",
                 type = "RPQ",
              address = "S{\~a}o Jos{\'e} dos Campos",
                 note = "{Bolsa PIBIC/INPE/CNPq.}",
             keywords = "equil{\'{\i}}brio qu{\'{\i}}mico, minimiza{\c{c}}{\~a}o da 
                         energia livre, combust{\~a}o, propuls{\~a}o, CEQ-INPE, chemical 
                         equilibrium, free energy minimization, combustion, propulsion.",
             abstract = "Este relat{\'o}rio descreve o programa de equil{\'{\i}}brio 
                         qu{\'{\i}}mico CEQ-INPE escrito na linguagem de 
                         programa{\c{c}}{\~a}o Python e desenvolvido para 
                         aplica{\c{c}}{\~o}es em combust{\~a}o e propuls{\~a}o. Para o 
                         desenvolvimento do c{\'o}digo foram inicialmente revisados 
                         conceitos de qu{\'{\i}}mica, combust{\~a}o, propriedades de 
                         misturas, termodin{\^a}mica, energias livres, constantes de 
                         equil{\'{\i}}brio, multiplicadores de Lagrange e sintaxe da 
                         linguagem Python. As condi{\c{c}}{\~o}es de equil{\'{\i}}brio 
                         para diferentes processos reativos considerados (HP, TP, UV, TV) 
                         foram determinadas com base na minimiza{\c{c}}{\~a}o direta da 
                         energia livre de Gibbs ou da energia livre de Helmholtz, 
                         referentes {\`a} mistura dos produtos das rea{\c{c}}{\~o}es, 
                         garantindo-se a conserva{\c{c}}{\~a}o dos {\'a}tomos com a 
                         aplica{\c{c}}{\~a}o da t{\'e}cnica dos multiplicadores de 
                         Lagrange. Os sistemas de equa{\c{c}}{\~o}es n{\~a}o lineares 
                         obtidos foram resolvidos por meio do m{\'e}todo de Newton-Raphson 
                         para v{\'a}rias dimens{\~o}es. O programa obt{\'e}m as 
                         propriedades de equil{\'{\i}}brio para rea{\c{c}}{\~o}es entre 
                         misturas de combust{\'{\i}}veis do tipo CHON e oxidantes do tipo 
                         HON, com raz{\~o}es de equival{\^e}ncia entre 0,1 e 3. O 
                         c{\'o}digo tamb{\'e}m apresenta uma interface gr{\'a}fica, com 
                         op{\c{c}}{\~o}es para entrada de dados e 
                         visualiza{\c{c}}{\~a}o dos resultados. A fim de se verificar a 
                         acur{\'a}cia do c{\'o}digo desenvolvido, os resultados obtidos 
                         com o CEQ-INPE foram comparados a resultados do programa CEA2-NASA 
                         (Chemical Equilibrium with Applications), verificando-se excelente 
                         concord{\^a}ncia para processos a press{\~a}o e entalpia 
                         constantes (HP), temperatura e press{\~a}o constantes (TP), 
                         energia interna e volume constantes (UV) ou temperatura e volume 
                         constantes (TV). ABSTRACT: The research carried out continues the 
                         previous scientific initiation project that developed a chemical 
                         equilibrium program written in Python language for reactive 
                         mixtures of ideal gases. In this project, reactions under 
                         different equilibrium conditions were considered: i) constant 
                         enthalpy and pressure (HP), ii) constant temperature and pressure 
                         (TP), iii) constant internal energy and volume (UV) and iv) 
                         temperature and constant volume (TV), for mixtures of CHON-type 
                         fuels and HON-type oxidants. The equilibrium composition of the 
                         products was obtained through the minimization of the Gibbs or 
                         Helmholtz free energies, for the processes at constant pressure or 
                         at constant volume, respectively. The ideal gas program has been 
                         completed, has a modern graphical interface and shows similar 
                         performance to NASA's chemical equilibrium program (CEA2 2004), 
                         for the equivalence ratios tested and number of products 
                         considered. In this new stage of research, the objective of the 
                         project is to create a chemical equilibrium program for real 
                         gases, considering the Redlich-Kwong equation of state. For this 
                         purpose, the minimization of the free energies of Gibbs or 
                         Helmholtz must be carried out based on the fugacity of real gases 
                         and the residuals of enthalpies, entropies and specific heats in 
                         relation to ideal gases must be calculated. The project is still 
                         in progress and this report is partial, containing only what has 
                         been obtained so far.",
          affiliation = "{Universidade Estadual Paulista (UNESP)} and {Instituto Nacional 
                         de Pesquisas Espaciais (INPE)}",
             language = "pt",
                pages = "32",
                  ibi = "8JMKD3MGP3W34T/457RSAH",
                  url = "http://urlib.net/ibi/8JMKD3MGP3W34T/457RSAH",
           targetfile = 
                         Relatorio_Final_PIBIC_2020_2021_Jose_Raimundo_da_Silva_Junior.pdf",
        urlaccessdate = "21 maio 2024"
}