CFD Online Discussion Forums

CFD Online Discussion Forums (http://www.cfd-online.com/Forums/)
-   CFX (http://www.cfd-online.com/Forums/cfx/)
-   -   Fluidized bed simulation VS particle tracking (http://www.cfd-online.com/Forums/cfx/90010-fluidized-bed-simulation-vs-particle-tracking.html)

windhair June 28, 2011 12:09

Fluidized bed simulation VS particle tracking
 
Hi, all

I'm currently simulate a fluidized bed with large amount of particles up to 70% volume fraction, as I read from the document, under such condition, particle tracing method does not work correctly anymore, since the particle method only works well when the volume of the particle is much less compare to the fluid volume, am I right?

So as the document suggested, I usr gas as fluid, solid part as dispersed fluid,and set a artificial viscosity for it. Additionally, the phenomena above the fluidized bed is transient, when I set the solid bed height with step function as the initial condition, the simulation can only run only one or two loop, and a INSUFFICIENT CATALOGUE SIZE error occurs.

Is this a problem of the CATALOGUS SIZE or there are something wrong with my fluidized bed simulation setup? what is the criticle point for a fluidized bed simultion? is there some example available?

Thank you .

ghorrocks June 28, 2011 19:06

Yes, a eularian approach would make sense here. Particle tracking is not suitable for such volume ratios.

Just increase the catalog size and it should go. Search the forum for how to increase the catalog size.

CFX support should have examples of fluidised bed simulations.

windhair June 28, 2011 21:10

Thank ghorrocks
yes, i just modified the catalogue size, hope it can run smoothly now.

BTW, about the particle simulation, do you have some idea about the difference between DMP (discrete particle method) and the euler-euler or euler-lagrange approach in CFX, i find many literature works about fluidized bed are using DPM method, any hints on this point? :)


All times are GMT -4. The time now is 16:48.