Smoothed Particle Hydrodynamics for Numerical Predictions of Primary Atomization

The design goal for future propulsion systems of civil aircrafts is to minimize the environmental impact as well as to optimize the economic benefit. At least for long range flights, liquid fuels will continue to be the preferred and most appropriate energy carrier. Minimizing harmful emissions and, at the same time, maximizing the efficiency of an aircraft engine may be thermodynamically contradictory. The key technology which enables both, low emissions and high efficiencies, is a well controlled combustion process. Controlling combustion mainly comprises a well defined fuel placement inside the combustion chamber.
However, the simulation of fuel atomization was not feasible due to the enormous computational requirements of this multi-scale problem and the accuracy required for a correct handling of multiphase flows. Presently, sophisticated combustion simulations still rely on fuel droplet starting conditions, which are a rather rough estimate of the real spray properties. Furthermore, the physical effects of air assisted atomization are not understood in detail.