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.

June 10, 2012, 06:50	Morphology	#1
mech-engineer New Member Behzad Join Date: Jun 2012 Posts: 26 Rep Power: 13	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.

Similar Threads
Thread	Thread Starter	Forum	Replies	Last Post
Dynamic meshing in CFX: (negative volume error)	vmlxb6	CFX	25	April 2, 2020 18:19
Morphology Divergence of a boundary patch field	ngj	OpenFOAM Running, Solving & CFD	42	June 3, 2015 09:46

June 11, 2012, 14:45		#2
victorwfreire New Member Victor Azevedo Join Date: Aug 2010 Posts: 5 Rep Power: 15	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.

June 11, 2012, 16:02		#3
mech-engineer New Member Behzad Join Date: Jun 2012 Posts: 26 Rep Power: 13	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?

June 11, 2012, 20:09		#4
ghorrocks Super Moderator Glenn Horrocks Join Date: Mar 2009 Location: Sydney, Australia Posts: 17,700 Rep Power: 143	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.