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-   -   How to decide interfacial length scale in Mixture Model of CFX multiphase simulation? (http://www.cfd-online.com/Forums/cfx/78199-how-decide-interfacial-length-scale-mixture-model-cfx-multiphase-simulation.html)

 TommySean July 15, 2010 03:50

How to decide interfacial length scale in Mixture Model of CFX multiphase simulation?

The help file of CFX solver theory guide says that for the mixture model the interfacial length scale must be specified. And an equation about calculating this d.ab from (r.a, r.b,d.a,d.b) is provided.

However, when both fluid are treated as continuous fluid, how do I get the d.a and d.b?

:confused:

 TommySean July 18, 2010 10:51

Help! Thank you!

 Zaktatir September 29, 2010 06:16

It does interest me 2.

 ghorrocks September 29, 2010 08:21

I do not know how to specify it. But if you do a sensitivity study you might find it does not matter anyway. If not you better work it out.

 haider760 March 20, 2012 06:51

Hi Tommy

Did you find out how to define mixture length scale for two continuous fluids?

 TommySean April 6, 2012 22:48

yeah

Quote:
 Originally Posted by haider760 (Post 350389) Hi Tommy Did you find out how to define mixture length scale for two continuous fluids?
The mixture length is just to provide a parameter to calculate the interfacial area. If both or at least one fluid is particle, it may be easy to understand how CFX calculate that interfacial area. The mixture length, can be taken as just another software interface that facilitates the user input. At the background, the CFX software will calculate another value for use in the computation.

I haven't used CFX for several months. If you can leave an email here, I'd like to send you some pictures that illustrates the effects of various mixture length or particle diameter settings.

 haider760 April 6, 2012 23:46