Development of a 300 KGF bypass hydrogen peroxide hybrid rocket system

The objective of this research is to establish a 300 kgf bypass liquid hydrogen peroxide hybrid rocket system, and the study includes theoretical calculation, bypass liquid hydrogen peroxide (HP) injection, HP pre-decomposition catalyst chamber design and hybrid rocket engine design. The purpose of using bypass liquid HP spray is to prevent the heat transfer from combustion chamber which may cause damage and failure to the swirl injector. The design of the catalyst chamber is based on the previous study of the HP mono-propellant thrusters and 30 kgf HP hybrid rockets in our laboratory. The determination of oxidizer flux of catalyst chamber, swirling injector, and length-diameter ratio (L/D) of the propellant are scaled up based on the previous successful results of the 30 kgf HP hybrid rocket. Flow visualization and cold gas are used to simulate the interaction of the decomposed gas and HP spray in the propellant port. The ignition location is estimated by varying different fuel grain lengths. Experimental results of the 300 kgf hybrid rocket system had shown that the ignition delay time is 0.3s, the average thrust is 300 kgf, and Isp is 220.75 s at sea level. The liquid injection successfully prevents the heat transfer from combustion chamber.