REGIMES FOR FLOW-BLURRING AND FLOW-FOCUSING ATOMIZATION OF NEWTONIAN AND NON-NEWTONIAN FLUIDS

Abstract

This paper presents a detailed mapping of flow-blurring (FB) and flow-focusing (FF) atomization as relevant to Newtonian fluids and non-Newtonian fluids. Two Newtonian fluids with different viscosities are tested, along with a non-Newtonian fluid, where the properties are similar to those of human saliva. Images featuring the fragmentation characteristics are presented with regime diagrams describing the transition from flow-focusing to flow-blurring. Flow-blurring refers to a mode of atomization where the fluid is partially aerated with gas bubbles to assist breakup, while flow-focusing has similarities to air-blast atomization (AB). The regime transition map developed for FF/FB atomizers reveals the parameters, which define transitions from the flow-focusing to the flow-blurring regime. Along with the transition identification, the breakup regime map also details the fragment morphology of the atomizing liquid stream as a function of the governing dimensionless groups.