%0 Journal Article %A Woodward, R. D. %A Burch, R. L. %A Cheung, Fan Bill %D 1994 %I Begell House %N 1-6 %P 365-378 %R 10.1615/IntJEnergeticMaterialsChemProp.v3.i1-6.380 %T REAL-TIME X-RAY RADIOGRAPHY STUDY OF LIQUID JET BREAKUP FROM ROCKET ENGINE COAXIAL INJECTORS %U https://www.dl.begellhouse.com/journals/17bbb47e377ce023,15629a1604e1b6b4,6271fae91ebdaffa.html %V 3 %X The investigation of liquid jet breakup and spray development is critical to the understanding of combustion phenomena in liquid-propellant rocket engines. A great deal of work has been done to characterize low-speed liquid jet breakup and dilute sprays, but atomizing jets and dense sprays have yielded few quantitative measurements due to their optical opacity. The present work focuses on a characteristic of the primary breakup process of round liquid jets, namely the length of the intact liquid core. The specific application considered is that of shear-coaxial-type rocket engine injectors. Real-time x-ray radiography, capable of imaging through the dense two-phase region surrounding the liquid core, is used to make the measurements. The intact liquid-core length data have been obtained and interpreted to illustrate the effects of chamber pressure (gas density), injected-gas and liquid velocities, and cavitation. The results show clearly that the effect of cavitation must be considered at low chamber pressures since it can be the dominant breakup mechanism. A correlation of intact core length in terms of gas-to-liquid density ratio, liquid jet Reynolds number, and Weber number is suggested. The gas-to-liquid density ratio appears to be the key parameter for aerodynamic shear breakup in this study. %8 1994-01-01