Experimental and Numerical Characterization of a Liquid Jet Injected into Air Crossflow with Acoustic Forcing

Abstract

This paper focus on the dynamic of a spray issued from the shearing of a liquid jet injected in an air crossflow submitted to high acoustic perturbations. Experimental and numerical approaches are used. Characterization of the liquid jet close to the injection location is obtained from high speed visualizations performed with a back lighting technique. Phase Doppler Anemometry gives useful information on the spray dynamics. The phase-averaged post processing method is chosen to describe the flow oscillations during the excitation cycle. The numerical simulation is performed with the multi-scale LES approach. This method couples a multi-fluid solver for the liquid jet body with a dispersed phase solver dealing with the atomized spray. The experimental results show a swigging phenomenon of the liquid jet and the existence of velocity and concentration waves travelling downstream of the liquid jet. Coupled phenomena between the crossflow, the atomization of the liquid jet and the transport of droplets are observed, revealing different wave transport velocities. The numerical simulation is able to capture the global swinging phenomenon of the liquid jet main body as well. A very good agreement is obtained for the jet trajectories oscillations obtained either by the simulation or from the experiment during the whole excitation cycle.

Numerical Simulation on Primary Breakup Characteristics of Liquid Jet in Oscillation Crossflow

“…Bodoc [19] found the periodic movement and breakup of a liquid column and the cyclic impact of a liquid jet on the upper wall of a channel and thus measured the time delays associated with each behavior. Desclaux et al [20] experimentally and numerically studied atomization in an oscillating gaseous crossflow. Their findings indicated that spray dynamics were influenced by both the oscillations of the liquid column and the crossflow, and the periodic flapping motion of the liquid column was induced by the acoustic fluctuating velocity.…”

A Study on Accounting for Drift Velocities on Liquid Jets Injected in Cross Flow

“…Therefore, advanced technologies have been developed. In order to achieve fine and uniform fuel droplet distribution, manufacturers of combustion chambers developed lean-burning combustion regimes to minimize pollutant formation [4], numerous investigations of the atomization process in constant air flow have been published in the literature. It was demonstrated how different parameters, such as the moment flux ratio or the Weber number, affect the liquid behavior [5,6,7].…”