Fechar
Metadados

@PhDThesis{Hennemann:2015:EsTePr,
               author = "Hennemann, Luciano",
                title = "Estudo te{\'o}rico-experimental de um propulsor monopropelente a 
                         {\'o}xido nitroso usando catalisador de r{\'o}dio suportado",
               school = "Instituto Nacional de Pesquisas Espaciais (INPE)",
                 year = "2015",
              address = "S{\~a}o Jos{\'e} dos Campos",
                month = "2015-02-20",
             keywords = "catal{\'{\i}}tico, {\'o}xido de r{\'o}dio, catalisador, 
                         catalytic, rhodium oxide, catalyst.",
             abstract = "O {\'o}xido nitroso {\'e} um monopropelente com uso potencial em 
                         sistemas de propuls{\~a}o de sat{\'e}lites. Este trabalho 
                         apresenta uma investiga{\c{c}}{\~a}o te{\'o}rico-experimental 
                         de um propulsor com empuxo de 2 N empregando {\'o}xido nitroso 
                         gasoso como monopropelente, decomposto por um catalisador 
                         suportado e com pr{\'e}-aquecimento do propelente e do 
                         catalisador por um sistema \emph{glow-plug}. Inicialmente foi 
                         realizado um estudo te{\'o}rico dos par{\^a}metros propulsivos e 
                         o dimensionamento do propulsor para opera{\c{c}}{\~a}o em 
                         condi{\c{c}}{\~a}o ambiente. Adotou-se um projeto modular 
                         permitindo o uso de leitos catal{\'{\i}}ticos de diferentes 
                         comprimentos e di{\^a}metros. Devido {\`a} sua efici{\^e}ncia 
                         de decomposi{\c{c}}{\~a}o, um catalisador com {\'o}xido de 
                         r{\'o}dio suportado em alumina foi preparado nos 
                         laborat{\'o}rios do INPE/LCP e usado para 
                         decomposi{\c{c}}{\~a}o do {\'o}xido nitroso. Os gr{\~a}os de 
                         catalisador eram extrudados cil{\'{\i}}ndricos com cerca de 2 mm 
                         de di{\^a}metro e 3 mm de comprimento. Foi realizada a 
                         constru{\c{c}}{\~a}o de prot{\'o}tipos com diferentes 
                         c{\^a}maras e foram executados testes de desempenho do propulsor. 
                         Uma bancada experimental existente foi adaptada para a 
                         realiza{\c{c}}{\~a}o dos testes e avalia{\c{c}}{\~a}o dos 
                         propulsores. Foram medidos o empuxo, vaz{\~a}o m{\'a}ssica de 
                         oxidante, al{\'e}m das press{\~o}es e temperaturas na linha de 
                         alimenta{\c{c}}{\~a}o e na c{\^a}mara do propulsor. A partir 
                         dos dados experimentais foram determinados os par{\^a}metros 
                         propulsivos como impulsos espec{\'{\i}}ficos, coeficientes de 
                         empuxo, velocidades caracter{\'{\i}}sticas e efici{\^e}ncias. 
                         Dois modelos computacionais foram desenvolvidos para descrever o 
                         funcionamento do propulsor. Um modelo unidimensional em regime 
                         permanente utilizando a Equa{\c{c}}{\~a}o de Ergun para meios 
                         porosos, com taxas de rea{\c{c}}{\~a}o homog{\^e}nea e 
                         heterog{\^e}nea, foi utilizado para simular a 
                         decomposi{\c{c}}{\~a}o do propelente e determinar a 
                         distribui{\c{c}}{\~a}o de temperaturas e a 
                         composi{\c{c}}{\~a}o final ao longo do leito 
                         catal{\'{\i}}tico. Um modelo t{\'e}rmico de par{\^a}metros 
                         concentrados, tamb{\'e}m considerando taxas de rea{\c{c}}{\~a}o 
                         homog{\^e}nea e heterog{\^e}nea, avaliou o comportamento 
                         transiente do escoamento e da distribui{\c{c}}{\~a}o de 
                         temperaturas no propulsor, permitindo simular o funcionamento 
                         pulsado do propulsor. As curvas de temperatura e demais dados dos 
                         modelos te{\'o}ricos foram comparadas {\`a}s curvas 
                         experimentais, obtendo-se razo{\'a}vel concord{\^a}ncia. 
                         ABSTRACT: Nitrous oxide is a monopropellant with potential for use 
                         in propulsion systems of satellites. This work presents a 
                         theoretical and experimental investigation of a 2N thruster 
                         prototype using gaseous nitrous oxide such as the monopropellant. 
                         The nitrous oxide is decomposed by a supported catalyst with 
                         pre-heating of the gaseous propellant and the catalyst by a glow 
                         plug. Initially a theoretical study of the propulsive parameters 
                         and the design of the engine for operation in ambient condition 
                         were performed. A modular design was adopted allowing the use of 
                         catalytic beds with different lengths and diameters. Due to its 
                         high decomposition efficiency, a rhodium oxide catalyst supported 
                         in alumina was prepared at LCP/INPE laboratories and used for 
                         nitrous oxide decomposition. Catalyst pellets had about 2 mm 
                         diameter and 3 mm length. Prototype thrusters with different 
                         chambers were manufactured and performance tests were made. An 
                         existing test bench was improved for testing and evaluation of the 
                         thrusters. The measured parameters included thrust level, mass 
                         flow of oxidizer, pressures and temperatures in the supply line 
                         and in the propellant chamber. From the experimental data the 
                         propulsive parameters such as specific impulse, thrust 
                         coefficients, characteristic speeds and efficiencies were 
                         determined. Two computational models were developed in order to 
                         reproduce the thruster behavior. A steady one-dimensional model 
                         using the Ergun equation for porous media flow, with homogeneous 
                         and heterogeneous reaction rates, was used to simulate the 
                         decomposition and to predict the final temperature and composition 
                         along the catalytic chamber. A lumped parameter thermal model, 
                         also considering homogeneous and heterogeneous reaction rates, 
                         described the transient behavior of the flow and temperature 
                         distribution during pulsed operation of the thruster. The 
                         theoretical curves of temperature and other properties from both 
                         models were compared with the curves obtained experimentally 
                         indicating reasonable agreement.",
            committee = "Costa, Fernando de Souza (presidente/orientador) and Savonov, 
                         Roman Ivanovitch and Soares Neto, Tur{\'{\i}}bio Gomes and 
                         Marchi, Carlos Henrique and Veras, Carlos Alberto Gurgel",
           copyholder = "SID/SCD",
         englishtitle = "Theoretical and experimental study of a monopropellant thruster 
                         with nitrous oxide using rhodium catalyst supported",
             language = "pt",
                pages = "177",
                  ibi = "8JMKD3MGP3W34P/3HQFEQ5",
                  url = "http://urlib.net/rep/8JMKD3MGP3W34P/3HQFEQ5",
           targetfile = "publicacao.pdf",
        urlaccessdate = "04 dez. 2020"
}


Fechar