Atomization of a 2D air-water mixing layer
(128 Mbytes, Daniel Fuster and Jérôme Hoepffner)
In this simulation a planar liquid layer is flowing under a faster gas layer. The simulation is described
in detail in Agbaglah et al. (2010), see references.
The simulation was performed using Gerris.
Lagrangian Particle Atomization Simulation (5 Mbytes, click on image to view movie). (Gaurav Tomar, Daniel Fuster, Stephane Popinet and Stephane Zaleski). In this simulation, small patches of fluid (two-dimensional "droplets" or rather cylinders) are transformed
into Lagrangian particles. Lagrangian particles follow a trajectory determined by the modelled particle forces (such as drag, lift and gravity, as well as several others). When a Lagragian particle collides with a large patch of liquid, its mass is transferred again to the "resolved" description. The resolved description uses the VOF tracking scheme. Details of the scheme are given in Tomar et al. (2010).
Atomization of a 3D jet
(13 Mbytes, Stéphane Popinet, Anne Bagué, Shricharan Yarlagadda and Stéphane Zaleski using the
Gerris code. This simulation reproduces closely the conditions in an automotive engine,
however the liquid jet is pulsed to trigger the instability in a more spectacular manner (Untriggered jets tend to have boring
behavior, see legacy simulations.
The Diesel fuel jet has a diameter under a millimeter
and a velocity over 100 meters/second. The Reynolds number is 5800. Air pressure is high at the relevant phase of the engine cycle
so the air to liquid density ratio is about 30. Oct-tree adaptive mesh refinement allows to have a resolution equivalent, in the
the finest grid regions, to that of a simulation with 16 billion grid points.
A similar simulation
can be reproduced following the Gerris example.