Numerical study on the morphology of a liquid-liquid pintle injector element primary breakup spray
Rui Zhou, Chibing Shen, Xuan Jin
Abstract
Primary breakup in a liquid-liquid pintle injector element at different radial jet velocities is investigated to elucidate the impingement morphology, the formation of primary breakup spray half cone angle, the pressure distribution, the liquid diameter distribution, and the liquid velocity distribution. With a sufficient mesh resolution, the liquid morphology can be captured in a physically sound way. A mushroom tip is triggered by a larger radial jet velocity and breakup happens at the tip edge first. Different kinds of ligament breakup patterns due to aerodynamic force and surface tension are captured on the axial sheet. A high pressure core is spotted at the impinging point region. A larger radial jet velocity can feed more disturbances into the impinging point and the axial sheet, generate stronger vortices to promote the breakup process at a longer distance, and form a larger spray half cone angle. Because of the re-collision phenomenon the axial sheet diameter does not decrease monotonically. The inner rim on the axial sheet shows a larger diameter magnitude and a lower velocity magnitude due to surface tension. This paper is expected to provide a reference for the optimum design of a liquid-liquid pintle injector.