Author:

Keywords:

Science & Technology, Technology, Physical Sciences, Engineering, Multidisciplinary, Engineering, Chemical, Engineering, Mechanical, Materials Science, Multidisciplinary, Physics, Applied, Engineering, Materials Science, Physics, LASER-BASED MEASUREMENTS, PROPANE JETS, ATOMIZATION, 0203 Classical Physics, 0904 Chemical Engineering, 0913 Mechanical Engineering, Mechanical Engineering & Transports, 4012 Fluid mechanics and thermal engineering

Abstract:

Experiments were carried out to obtain spray drop velocity and size measurements when high-pressure fluid is injected into near-vacuum conditions typically observed downstream from rocket engine injectors and venting devices of the upper stages of spacecraft. Three different liquids representative for spacecraft propellants are investigated for injection at or near flashing conditions. Up to three typical injector geometries are evaluated at different pressure ratios and flow rates. The results show how flash atomization in vacuum conditions modifies the spray pattern, increases droplet velocities, and decreases their size compared with nonflashing conditions. From these results, several drop size and velocity correlations were established for the different injectors according to injection velocity and superheat level. © 2009 Begell House, Inc.