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Helal April 17, 2001 01:14

Eulerian vs Lagrangian
 
Can anybody explain the basic differences between the Eulerian and Lagrangian Particle Tracking?

Regards,

Helal

Jan Rusås April 17, 2001 07:12

Re: Eulerian vs Lagrangian
 
In the Eulerian approach is both the fluid/gas and the particles treated as continuum and continuum equations are solved for both phases with an appropriate interaction. In the Lagrangian approach, is the fluid/gas still treated as continuum, but the particulate phase is treated as single particles, where particle trajectories, representing a stream of particles, are calculated as a result of forces acting on them.

The Eulerian model is typically used, when there are many particles, high mass loading,.

Hope it helps

Regards Jan

Helal April 17, 2001 20:53

Re: Eulerian vs Lagrangian
 
Dear Jan,

Many thanks for your excellent explanations.

Could you please explain which approach is suitable for coal combustion modelling?

In CFX4 Lagrangian approach has been used.

Regards,

Helal

Dan Williams April 18, 2001 00:00

Re: Eulerian vs Lagrangian
 
Seems to me that this would depend on what part of the coal combustion modelling you are interested in simulating.

If you are interested in the region near a nozzle outlet, where the particles might behave as a single fluid, then an eulerian model would probably be fine. In addition to that, the particles must also be of roughly uniform diameter (which is probabably not the case).

However, if you are wanting to simulate regions further from an injection port, where the particles have spread out a fair bit, and will likely have a uneven spread of particle diameters then a lagrangian approach is likely the better candidate.

CFX-4 can do either.

Dan.


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