Spray formation by like-doublet impinging jets in low speed cross-flows

Abstract

Breakup and spray formation by impinging liquid jets introduced into a low-speed cross-flow are experimentally investigated. Effects of the cross-flows on the macroscopic and microscopic spray parameters are optically measured in terms of jet Weber number and liquid-to-gas momentum ratio. The liquid stream undergoes Rayleigh jet breakup at lower jet Weber numbers and bag/plume breakup at higher momentum ratio through Kelvin-Helmholtz instability. In particular, the first and the second wind breakup occur at an intermediate jet Weber number. At higher jet Weber numbers, the hydrodynamic impact waves commands and the effect of the convective gas flows is insignificant. The breakup length rises in proportion to the jet Weber number, but starts to decrease when the jet Weber number further rises over 1000. The cross-flow promotes the jet breakup and renders a finer spray in an entire range of injection velocities.

Impingement of liquid jets at atmospheric and elevated pressures: an observational study using paired water jets or water and methylcyclohexane jets

“…Besides application-oriented studies, such as those cited earlier, a number of fine fluid-mechanical studies have been performed to explore the nature of formation and disintegration of geometrically beautiful liquid sheets resulting from the oblique or coaxial collision of equal cylindrical jets and/or to investigate the characteristics of liquid atomization available by such collisions (see Dombrowski & Fraser 1954;Taylor 1960;Dombrowski & Hooper 1962, 1963Huang 1970;Ibrahim & Przekwas 1991;Anderson et al 1992;Kang et al 1995;Ryan et al 1995;Shen & Poulikakos 1998;Choo & Kang 2001Bush & Hasha 2004;Bremond & Villermaux 2006;Li & Ashgriz 2006;Ibrahim & Outland 2008;Lee et al 2009). Most of these studies dealt with the impingement in air under atmospheric pressure (approx.…”