Numerical simulations of acoustically excited spray atomization

The efficiency of a gas turbine is largely dependent on the combustion process between the liquid fuel and the oxidizer. The mixing of the the fuel vapours and the incoming air is critical to the combustion process, and the primary factor affecting vaporization is the atomization of the fuel spray. Experiments [1] have shown that high-amplitude acoustic waves are effective in controlling breakup and enhancing atomization of liquid sprays. We perform numerical simulations to investigate the dynamics of spray breakup of a water jet in the presence of transverse, standing acoustic waves. In agreement with experiments, it is observed that high-amplitude sound waves ~170 dB can have a significant effect on spray atomization. The jet location along the standing wave generated in the chamber is found to be a major factor affecting breakup and atomization. The compressible flow equations are solved, and the multiphase treatment uses a Volume of Fluid (VOF) approach with a piecewise linear interface calculation (PLIC) for the interface reconstruction.

[1] Ficuciello, A., Blaisot, J., Richard, C., and Baillot, F. Physics of Fluids, 29(6):067103, 2017.