Understanding the primary breakup characteristics of impingement of a liquid jet on an opposing gas jet

We present the results of a computational investigation of the primary breakup characteristics of the impingement of a liquid jet on an opposing gas jet. The numerical simulation of the three-dimensional configuration was performed by employing the volume-of-fluid method with adaptive mesh refinement to visualize the rupture of the liquid sheet, flow patterns, and ligament formation from the liquid sheet. The results presented are in agreement with our numerical results and existing experiments. We observed the primary breakup and atomization characteristics of a liquid jet impinging on the gas jet for dimensionless numbers such as the momentum ratio between the gas and liquid jets (X), the Reynolds number (Re), and the Weber number (We). In addition, this study classified the Weber number into low, intermediate, and high to highlight the distinct breakup regimes. We identified the breakup length and number of ligaments for a range of X, We, and Re. We also discuss the effect of the Rayleigh–Taylor (RT), Kelvin–Helmholtz (KH), and Plateau–Rayleigh (PR) or capillary instability mechanisms. A regime in the We−Re plane is shown to highlight the transition from the turbulent parachute to the turbulent sheet regime for different values of X. These results lay the foundation for optimizing spray systems in several industrial applications that rely on atomization.