Ignition and combustion performance of the primary condensed-phase combustion products from boron-based fuel-rich propellants

The primary condensed-phase combustion products of a boron-based fuel-rich propellant were ignited using a high-power CO₂ laser in a pressurized and windowed combustion chamber under variable pressure. The ignition and combustion performances were characterized using an ultraviolet-visible spectrometer and a high-speed camera. The experimental results showed that the combustion of the condensed-phase combustion products originate from the combustion of carbon, and boron may not take any part in the combustion process because of the formation of a thick boron oxide coating and agglomeration after the primary combustion process. Both particle size and the ingredients play an important role in the combustion reaction of the condensed-phase products. It was observed that a lower particle size and a higher boron carbide content are beneficial for the combustion reaction of the products; higher primary and secondary combustion pressures clearly improved the secondary combustion efficiency of the propellant in the combustion reaction.