76th Annual Meeting of the APS Division of Fluid Dynamics (November 19, 2023 — November 21, 2023)

V0025: Direct numerical simulation of twin-fluid atomization in the annular flow regime

Authors

• Bradley Boyd, Department of Mechanical Engineering, University of Canterbury, New Zealand
• Sid Becker, Department of Mechanical Engineering, University of Canterbury, New Zealand
• Chang Liu, State Key Laboratory of High Temperature Gas Dynamics, Institute of Mechanics, Chineses Acedemy of Sciences, China
• Xuejun Fan, State Key Laboratory of High Temperature Gas Dynamics, Institute of Mechanics, Chineses Acedemy of Sciences, China
• Kun Wu, State Key Laboratory of High Temperature Gas Dynamics, Institute of Mechanics, Chineses Acedemy of Sciences, China

DOI: https://doi.org/10.1103/APS.DFD.2023.GFM.V0025

Three-dimensional direct numerical simulations of a twin-fluid atomizer in the annular regime are performed to study the multiphase instabilities, shock waves, and the onset of atomization. The injection involves a sonic air jet surrounded by an annular layer of liquid. The expansion of the sonic jet results in shock wave formations, Rayleigh–Taylor, and Kelvin-Helmholtz instabilities that cause the annular liquid sheet disintegration into ligaments and droplets. Three simulations at varying driving pressure; 0.55 MPa, 0.8 MPa, and 1.2 MPa, showed an interesting change in the dimensions of the mach disk shock-wave as well as the deformation of the liquid sheet.