%0 Journal Article %A Yuasa, Saburo %A Kitagawa, Koki %A Sakurazawa, Toshiaki %A Kumazawa, Ikuno %A Sakurai, Takashi %D 2011 %I Begell House %K LOX, vaporization, regenerative-cooling nozzle, swirling oxidizer, PMMA %N 2 %P 155-168 %R 10.1615/IntJEnergeticMaterialsChemProp.2012001351 %T LIQUID OXYGEN VAPORIZATION TECHNIQUES FOR SWIRLING-OXIDIZER-FLOW-TYPE HYBRID ROCKET ENGINES %U https://www.dl.begellhouse.com/journals/17bbb47e377ce023,57e9500f714490c3,2111d7e177472d24.html %V 10 %X The authors have been developing a 1500 N-thrust, swirling-oxidizer-flow-type hybrid rocket engine. The oxygen to which swirl is applied should be in a gaseous state to increase the engine performance. Two methods were proposed to vaporize liquid oxygen (LOX): a regenerative-cooling LOX-vaporization nozzle and a LOX-vaporization burner. We fabricated a LOX-vaporization nozzle with 30 rectangular channels, each with a depth of 1.0 mm, and conducted burning experiments. The experiments showed that rapid ignition and stable combustion without combustion oscillation were achieved, and LOX increased in temperature and sufficiently vaporized while passing through the nozzle. There was no essential problem in vaporizing LOX with the nozzle. The feasibility of the LOX-vaporization burner using combustion of polymethyl methacrylate (PMMA) in LOX was examined from the viewpoint of thermal energy and a preliminary burning experiment was conducted. The burning amount of PMMA to vaporize the LOX propellant for a 1500-N-thrust, hybrid rocket engine was estimated to be at most 3% of the fuel propellant of the rocket. PMMA could burn steadily and safely in LOX and vaporize a large amount of it. The trade-off between the two methods suggested that the vaporization burner had the advantage of a compact and simple structure when compared with the LOX-vaporization nozzle. %8 2012-06-29