Numerical Study of Free Liquid Jet Primary Breakup Phenomenon in Still Gases

Abstract

The present paper consists of a numerical investigation carried out for primary break up analysis of a vertical water jet. Many parameters impact the flow development such as velocity, turbulence and nozzle shape. In this work, two types of nozzle geometries have been performed, the first is a capillary circular and the second is conical. The calculations have been performed using the CFD Code Fluent of ANSYS, considering laminar and turbulent flow regimes. While turbulence was modelled using RNG k-ε of RANS approach. The main results show that the jet evolves differently in the two considered nozzle geometries comparing the jet intact lengths, drop sizes and distance between successive drops. It is observed that the turbulence increases substantially the jet intact length and enables the jet breakup at the lower part of the water column. For the conical nozzle case, the jet instabilities grow quickly resulting a drop size in the same order of the jet diameter and an intact length larger in comparison with the circular nozzle case.