NUMERICAL INVESTIGATION OF INCLINED LIQUID JET UNDER CROSS FLOW

Liquid jet in cross flow (LJICF) occurs in many applications such as sanitizer spray subject to surface wind, agricultural sprays, fuel spray in gas turbine combustion chambers, etc. In agricultural sprays subjected to cross flow, smaller droplets are often deposited off-target, which is known as spray drift. This is undesirable as the pesticide does not get applied to the target crop and causes harm at the non-target site. The liquid breakup length and the droplet size affect the droplet trajectory. It is reported that droplet size also depends on the injection angle with respect to the cross flow air. Therefore, drift can be controlled in a cross flow by adjusting the angle of injection relative to cross flow. Agricultural sprays are generally characterized by low Weber number and limited literature is available on low Weber number sprays. In the present work, the effect of injection angle on diameter distribution of the droplets and their trajectory for a low Weber number spray is investigated using computational fluid dynamics (CFD). Turbulence is modeled using Reynolds Averaged Navier-Stokes (RANS) approach and the discrete phase is modeled Euler-Lagrange approach, using ANSYS FLUENT. The effect of different primary breakup models (single point injection, plain orifice model) as well as secondary breakup models (TAB and KHRT) is studied. The Sauter Mean Diameter (SMD) and droplet velocity are investigated for different injection angles. The results show qualitative agreement with the experimental data available.