Publicado 6 números por año
ISSN Imprimir: 2150-766X
ISSN En Línea: 2150-7678
Indexed in
COMBUSTION PHENOMENA OF THE GUN PROPELLANT JA2
SINOPSIS
The experimental investigations concern the combustion phenomena of the standard gun propellant JA2, which are analyzed by a simplified model. The energy transfer from the gaseous phase governs the ignition and the combustion of solid rocket and gun propellants. In addition to the heat conduction and convection, the radiation of the flame contributes to the heat feedback, which controls the burning rate in dependence on pressure. The dependence on the initial temperature is given by physical parameters of the conversion from the solid to the gaseous state. Burning rates are measured in dependence on pressure and initial temperature confirming a simplified law for the burning rate. The evaluation yields that the pressure exponent can be directly assigned to the heat feedback and that the temperature of the conversion from the condensed to the gas phase lies at about 675 K. The experiments also comprise spectroscopic measurements at low pressures in the wavelength ranges from 300 nm to 14000 nm, which are resolved spatially along the vertical flame profile. The analysis of the spectra delivers the profiles of species in the flames including di-atomic radicals and tri-atomic molecules of the final combustion products. In addition, gas phase temperatures are derived by the application of the Single-Line-Group model, which gives approximately 2800 K closely below the adiabatic flame temperature of 2900 K at low pressures. They are compared to temperatures assigned to soot particle emission. The evaluated data enable an estimation of the heat feedback from the flame to the burning surface.