CFD Online Discussion Forums

CFD Online Discussion Forums (
-   CFX (
-   -   Morphology (

mech-engineer June 10, 2012 06:50

Hi dear friends
Which of the below morphologies is appropriate for modeling of nanparticles in a two-phase Eulerian nanofluid incluiding nanoparticles (copper oxide) and base fluid (water)?
1)Continuous Fluid
2)Dispersed Fluid
3)Dispersed Solid
4)Continuous Solid
Pls help me,it's very important for me.

victorwfreire June 11, 2012 14:45

I'm not very familiar with "nanotechnologies" (I don't know if writes this way). But, let me try to understand your problem. You have nano-particles in a nano-fluid, and all this mixture is imersed in water?

You could try two different modelling. You could develop one model for the nano-particles in the nano-fluid, for this you could model as a continuous-dispersed fluid-solid flow. After this, you can take the results for this model and apply to the other model (nano-fluid in water), if it's the case. you can also use the continuous-dispersed model, but now considering the dispersed fluid instead of dispersed solid.

Hope this can help.

mech-engineer June 11, 2012 16:02

No,you don't understand correctly the problem,The set of nanoparticles and base fluid is nanofluid.(nanofluid=base fluid+nanoparticle).My problem is another,namely,which morphology is appropriate for base fluid and which morphology is appropriate for nanoparticles to simulate two-phase nanofluid via Eulerian-Eulerian method?

ghorrocks June 11, 2012 20:09

The answer is that (most probably) none of your options are appropriate. Multiphase modelling is aimed for mixing at the micro scale. Nano scale processes have very different physics, where things like Brownian motion are important, and things like inter-phase slip are negligible.

There have been a lot of questions on the forum recently about what multi-phase model is best for nano particle modelling. It must be flavour of the month I guess.

So, before I can answer your question I need to know some details:
* Will the nanoparticles show significant slip relative to the fluid? Probably not at this scale.
* Is Brownian motion important? Probably.
* Does the nanoparticles affect the bulk fluid properties? If so, how?

In general the best approach for this type of model appears to be using an additional variable to model nanoparticle concentration, and diffusion to model Brownian motion. Material property changes can be made a function of the AV.

All times are GMT -4. The time now is 17:59.