Analysis of the temperature sensitivity of double-base propellants

Abstract

The temperature sensitivity of the burning rate of double-base propellants was studied to determine the parameters which control the temperature sensitivity mechanism. The temperature sensitivity of high and low energy propellants was examined in the temperature range between −30°C and +70°C. Experimental results indicated that the temperature sensitivity decreases as the energy contained in the unit mass of propellant increases. The burning surface temperature and the temperature in the fizz zone increased when the initial propellant temperature increased at a constant pressure. Thus, when the reaction rate in the fizz zone increased, the heat feedback from the gas phase to the burning surface increased. Consequently, the burning rate increased with increase in the initial propellant temperature. The heat released at the burnign surface remains relatively unchanged when the initial propellant temperature is increased. The temperature sensitivity of the burning rate is determined by the two parameters: “temperature sensitivity of the gas phase” and “temperature sensitivity of the condensed phase.” The temperature sensitivity of the gas phase can be decreased by decreasing the activation energy of the fizz zone reaction and/or by increasing the temperature in the fizz zone. The temperature sensitivity of the condensed phase can be decreased by increasing the burning surface temperature. These characteristics were confirmed by temperature sensitivity measurements of high and low energy propellants.