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@PhDThesis{GouvÍa:2017:EsQuPo,
               author = "Gouv{\^e}a, Leonardo Henrique",
                title = "Estudo da queima de polietileno e de combust{\'{\i}}veis {\`a} 
                         base de parafina com solu{\c{c}}{\~o}es de per{\'o}xido de 
                         hidrog{\^e}nio",
               school = "Instituto Nacional de Pesquisas Espaciais (INPE)",
                 year = "2017",
              address = "S{\~a}o Jos{\'e} dos Campos",
                month = "2016-11-16",
             keywords = "propuls{\~a}o h{\'{\i}}brida, per{\'o}xido de hidrog{\^e}nio, 
                         polietileno, parafina, taxa de regress{\~a}o, hybrid propulsion, 
                         hydrogen peroxide, polyethylene, paraffin fuel, regression rate.",
             abstract = "Sistemas de propuls{\~a}o h{\'{\i}}brida apresentam maior 
                         seguran{\c{c}}a de opera{\c{c}}{\~a}o, menor complexidade de 
                         projeto e menores custos de desenvolvimento e de 
                         opera{\c{c}}{\~a}o que sistemas a bipropelentes 
                         l{\'{\i}}quidos. Uma das limita{\c{c}}{\~o}es dos sistemas de 
                         propuls{\~a}o h{\'{\i}}brida s{\~a}o os reduzidos empuxos 
                         decorrentes das baixas taxas de regress{\~a}o dos propelentes 
                         polim{\'e}ricos convencionais. O polietileno (PE) {\'e} um 
                         combust{\'{\i}}vel h{\'{\i}}brido convencional que apresenta a 
                         forma{\c{c}}{\~a}o de uma camada l{\'{\i}}quida de alta 
                         viscosidade durante a queima e apresenta taxas de regress{\~a}o 
                         superiores {\`a}s do polibutadieno hidroxilado (HTPB) e do 
                         polimetil-metacrilato (PMMA). As taxas de regress{\~a}o de 
                         propelentes {\`a} base de parafina s{\~a}o de 3 a 5 vezes 
                         maiores que as taxas de regress{\~a}o do polietileno, uma vez que 
                         se forma uma camada l{\'{\i}}quida de baixa viscosidade na 
                         superf{\'{\i}}cie do gr{\~a}o, gerando gotas que s{\~a}o 
                         misturadas ao fluxo de oxidante. O per{\'o}xido de 
                         hidrog{\^e}nio {\'e} um green propellant com alta densidade que 
                         se decomp{\~o}e acima de 800 \$^{o}\$C em 
                         concentra{\c{c}}{\~o}es maiores que 90 \% m/m em 
                         solu{\c{c}}{\~a}o aquosa. Uma c{\^a}mara de combust{\~a}o com 
                         janela de quartzo foi projetada e constru{\'{\i}}da para o 
                         estudo da queima de combust{\'{\i}}veis polim{\'e}ricos com 
                         per{\'o}xido de hidrog{\^e}nio em concentra{\c{c}}{\~o}es de 
                         85 e 90 \%. Um leito catal{\'{\i}}tico de {\'o}xidos de Co, Mn 
                         e Al foi utilizado para decomposi{\c{c}}{\~a}o do per{\'o}xido 
                         e inje{\c{c}}{\~a}o dos produtos da decomposi{\c{c}}{\~a}o na 
                         c{\^a}mara de combust{\~a}o. Gr{\~a}os de se{\c{c}}{\~a}o 
                         retangular de polietileno e de combust{\'{\i}}veis {\`a} base 
                         de parafina foram preparados e queimados para an{\'a}lise da 
                         varia{\c{c}}{\~a}o espacial e temporal da taxa de 
                         regress{\~a}o. Observou-se a forma{\c{c}}{\~a}o de uma pequena 
                         eleva{\c{c}}{\~a}o na entrada da porta dos gr{\~a}os de 
                         polietileno, gerando uma zona de recircula{\c{c}}{\~a}o 
                         adjacente. Combust{\'{\i}}veis {\`a} base de parafina foram 
                         queimados com diferentes aditivos, verificando-se que a parafina 
                         impregnada com fios de algod{\~a}o apresenta o melhor desempenho 
                         em termos de igni{\c{c}}{\~a}o e estabilidade de queima. 
                         ABSTRACT: Hybrid propulsion systems have higher security 
                         operation, less complex design and lower operational and 
                         developmental costs than liquid bipropellant systems. One of the 
                         limitations of hybrid propulsion systems are the reduced thrust 
                         levels resulting from the low regression rates of common polymeric 
                         propellants. Polyethylene (PE) is a conventional hybrid fuel which 
                         presents the formation of a liquid layer of high viscosity during 
                         firing and shows regression rates higher than hydroxyl-terminated 
                         polybutadiene (HTPB) and polymethyl methacrylate (PMMA). 
                         Regression rates of paraffin-based propellants are 3 to 5 times 
                         higher than polyethylene regression rates, since paraffin forms a 
                         low viscosity liquid layer on the surface of the grain generating 
                         droplets that entrain the oxidant flow. Hydrogen peroxide is a 
                         high-density green propellant which decomposes above 800 
                         \$^{o}\$C for concentrations in aqueous solutions higher than 
                         90\% w/w. A combustion chamber with a quartz window was designed 
                         and built for the study of polymeric fuels burning with hydrogen 
                         peroxide in concentrations of 85 and 90 \%. A catalytic bed of 
                         Co, Mn and Al oxides were used for decomposition of the peroxide 
                         and injection of decomposition products into the combustion 
                         chamber. Rectangular grains of polyethylene and paraffin-based 
                         fuels were prepared and burned for analysis of the spatial and 
                         temporal variation of the regression rate. There was the formation 
                         of a lump at the port entrance of the polyethylene grains, 
                         creating an adjacent recirculation zone. Paraffin-based fuels were 
                         burned with different additives, and the impregnated paraffin wax 
                         with cotton threads showed the best performance in terms of 
                         ignition and burning stability.",
            committee = "Costa, Fernando de Souza (presidente/orientador) and Marques, 
                         Rodrigo Intini and Nunes, Renato Felix and Martins, Cristiane 
                         Aparecida and Veras, Carlos Alberto Gurgel",
           copyholder = "SID/SCD",
         englishtitle = "Study of burning polyethylene and paraffin based fuels with 
                         hydrogen peroxide solutions",
             language = "pt",
                pages = "190",
                  ibi = "8JMKD3MGP3W34P/3MPKMQP",
                  url = "http://urlib.net/rep/8JMKD3MGP3W34P/3MPKMQP",
           targetfile = "publicacao.pdf",
        urlaccessdate = "27 nov. 2020"
}


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