RESEARCH NEWS: ONDULATIONS, WAVES, DROPS, FROM THE VIRTUAL TO THE REAL

Published in 2013 in Journal of Fluid Mechanics


Alain Cartellier (LEGI)
Alain Cartellier (LEGI)

Researchers from the laboratory LEGI and their colleagues from the Virtual Assisted Atomisation Consortium have taken a big step towards the simulation of the complex flow instabilities occuring in gas assisted injection systems.

When a high speed gas flow impacts upon a liquid, we witness the formation of undulations, waves and droplet. Atomisation phenomena, commonly observed at the crests of waves, are a key principle of a number of propulsion systems. The efficiency and the reliability of such engines directly depend on the characteristics and the behaviour of the droplets produced.

By combining the results of controlled experiments with direct numerical simulations, researchers from the “Virtual Assisted Atomisation” consortium have developed a model to better understand where the droplets are formed and in what amount, as well as to calculate their size and velocity.

This leading-edge numerical code gives unprecedented access to the computation of severe flow conditions, equivalent to those encountered in gas assisted injection systems used in aeronautic propulsion. The VAA consortium is now actively working on the optimisation of the code with the aim of reducing the computational time.

Video: Air assisted atomisation of liquid films: experiments and simulations within the VAA project from the partner laboratories LEGI, IJLRDA, CORIA and IMFT


Ref: Fuster D, Matas JP, Marty S, Popinet S, Hoepffner J, Cartellier A and Zaleski S, Instability regimes in the primary breakup region of planar coflowing sheets, J. Fluid Mech., 736 150-176 (2013)