Experimental investigation of the axial oxidizer injectors geometry on a 1-kN paraffin-fueled hybrid rocket motor

The showerhead is the most common type of injector used in hybrid rocket motors due to its design and manufacture simplicity. main drawback showerheads (SH) relatively low performance terms combustion efficiency because poor atomization liquid oxidizer. This study investigates problem enrich technical literature by presenting detailed experimental data on injectors a series static firing tests using 1-kN lab-scale rocket, applying four kinds injectors, named SH1 (benchmark), SH2, SH3, SH4. They differ from each other number, distribution, dimension orifice elements. Main parameters such as fuel regression rate, specific impulse, are experimentally obtained. Two different were carried out. At first, influence SH geometries was studied. SH4 under same initial conditions, results compared with SH1. In second set tests, chosen, effects grain port diameter investigated. Using obtained battery possible determine motor establish rate law nitrous oxidizer/paraffin-based for this configuration.