Effect of Metal Addition on the Ignition Characteristics of a Pyrotechnic Igniter

Pyrotechnic igniters are used to ignite the small solid propellant motor. The combustion of the pyrotechnic igniter plays an important role in building the pressure inside the combustion chamber of the solid rocket motor. The igniter should be able to generate pressure in the combustion chamber in a fraction of the time and should be efficient. This research paper examines the effectiveness of two metal fuels, magnesium and aluminum, in combination with potassium nitrate as an oxidizer for pyrotechnic igniters used in small solid propellant motors. The fuel-to-oxidizer ratio is maintained at 50:50. The study reveals that the Mg/KNO₃ igniter mixture outperforms the Al/KNO₃ mixture in calorific value, with a 7406.32 kJ/kg value. However, it is to be noted that the incomplete combustion of the Al/KNO₃ mixture leads to a higher gas generation compared to the Mg/KNO₃ mixture. These findings underscore the significance of selecting the appropriate metal fuel for pyrotechnic igniters to optimize performance, considering factors such as calorific value and combustion completeness. The outcomes of this research contribute to developing and improving solid rocket motor efficiency.