Numerical Simulation of Liquid Jet Atomization Including Turbulence Effects

Abstract

This paper describes numerical implementation of a newly developed hybrid model, T-bbb/7'-TAB, into an existing computational fluid dynamics (CFD) program for primary and secondary breakup simulation of liquid jet atomization. This model extend two widely used models, the Kelvin-Helmholtz (KH) instability of Reitz (blob model) and the Taylor-Analogy-Breakup (TAB) secondary droplet breakup by O'Rourke and Amsden to include turbulence effects. In the primary breakup model, the level of the turbulence effect on the liquid breakup depends on the characteristic scales and the initial flow conditions. For the secondary breakup, a n additional turbulence force acted on parent drops is modeled and integrated into the TAB governing equation. Several assessment studies are presented and the results indicate that the existing KH and TAB models tend to under-predict the product drop size and spray angle, while the current model provides superior results when compared with the measured data.

Review of gas atomisation and spray forming phenomenology

“…Recently, atomization modelling has focused on stochastic simulation of the liquid jet and primary atomization in terms of Reynolds averaged Navier-Stokes mixing 7 and on turbulent atomization conditions. [8][9][10][11][12] The phenomenology of the atomization process, however, is both instructive and intriguing. It has produced a wealth of functional models, [13][14][15][16][17][18][19][20][21] that address atomisation parameters such as the nature of the gas and melt phase, gas injection pressures and melt superheat.…”

“…Recently, atomization modelling has focused on stochastic simulation of the liquid jet and primary atomization in terms of Reynolds averaged Navier-Stokes mixing 7 and on turbulent atomization conditions. 8–12…”

Spray Forming of al Alloys: experiment and theory

“…Recently, the more realistic cases of turbulent atomization conditions have been addressed, e.g. by CFD [23][24][25] and integrated models 17,34 have been proposed. This study considers the case of close coupled atomization of Al alloys and builds upon a theoretical two-phase model for melt fragmentation 32 .…”