Validation and Analysis of primary atomization of turbulent liquid jet in crossflow simulations

Abstract : This paper presents the results from direct numerical simulations of the primary atomization of a turbulent liquid jet injected into liquid crossflow. The simulations are performed for an experimentally analyzed configuration of Brown and McDonell (2006, "Near Field Behavior of a Liquid Jet in a Crossflow ", ILASS Americas, 19th Annual Conference on Liquid Atomization and Spray Systems). The turbulent liquid jet (q = 6.6, Re = 14 000, We = 2178) is injected into a subsonic gaseous crossflow (Re = 570 000, We = 330). The liquid/gas interface is captured using a coupled level set volume of fluid (CLSVOF) method. The jet penetration obtained from the simulations show good agreement with the experimental correlations and also to the findings from the literature. Two breakup mechanisms are observed: column breakup mode in which waves on the windward side of the jet propagate, roll up and form bag-like structures until they breakup; and ligament breakup mode caused by the corrugations of the liquid core surface forming thin ligaments on the liquid jet sides that subsequently breakup into droplets. Analysis of the crossflow velocity component of the liquid packets from the simulation shows that a number of liquid packets exist in the domain whose velocities are same as that of the gaseous crossflow.