Modelo matemático de câmaras de combustão bipropelentes / Mathematical model of bipropellant combustion chambers
AUTOR(ES)
Cesar Addis Valverde Salvador
DATA DE PUBLICAÇÃO
2004
RESUMO
A mathematical model of the combustion chamber of a liquid propellant rocket was developed. The combustion process is assumed to be one-dimensional and controlled by the vaporization of the droplets, since the rates of mixture and reaction in the gaseous phase are fast in comparison to the vaporization rates of the propellants. It was considered a non uniform distribution of droplets at the entrance, the preheating and thermal expansion of the droplets, the heat losses by convection and radiation from the hot gases to the walls and to the droplets, the gas-droplet relative velocity and the effects of droplet deformation on drag. The effects of pressure, temperature, equivalence ratio, number of groups of drops at the entrance and of the Rosin-Rammler parameters on the distance for complete vaporization were analysed. It was found that the radiation heat losses to the droplets are not significant compared to the convection losses, while the radiation losses to the chamber walls are significant. The vaporization distance and external wall temperature close to the injector were calculated and compared to experimental data from a 200 N thruster. The performance of bipropellant systems N2H4/N2O4, MMH/N2O4 and UDMH/N2O4 and multipropellant systems N2H4-MMH/N2O4 and N2H4-UDMH/N2O4 were analysed and compared.
ASSUNTO(S)
rocket engines câmara de combustão mathematical models propulsÃo combustion combustÃo propulsion modelos matemáticos hydrazines liquid fuels combustion chamber combustível líquido hidrazinas motor de foguete
