Entrainment Characteristics of a Swirling Liquid Jet

Entrainment and mixing are desirable in many chemical reactors and combustion chamber applications. Here, we explored the near-field entrainment characteristics in a swirling liquid jet injected into an ambient gaseous phase. Three-dimensional numerical simulations have been carried out for a range of swirl numbers 0.5 < S < 1.55. The main objectives of the present work are to understand the impact of recirculation zones on the entrainment characteristics of the swirling jet at a moderate Reynolds number of Re = 50 and Re = 100. The results indicate that the entrainment is enhanced at a higher swirl number for a constant Reynolds number. The maximum entrainment has been found to occur at the shear layer between liquid jet and ambient air. It is also observed that the ambient air experiences a toroidal recirculation in the flow field, which causes the ambient air to penetrate through the liquid–air interface.