[evcelica]

Originally Posted by S_teph_2000

Hello,

I just attended a seminar on ANSYS 15.0 release, just like the one I attended last year for ANSYS 14.5. I don't know if it's only me, but I have the strong feeling that little by little, CFX is left behind. every year, Fluent gets new capabilities, while CFX only gets a few updates here and there. As a CFX user it is really frustrating, especially when you're not doing much turbomachinery analysis... Is there still something, a good thing that is exclusive to CFX except the turbo machinery friendly part? because even if that's the case, I have the feeling it won't last.
Any thoughts ?

I know exactly what you mean, and I feel the same way sitting through the ANSYS "Fluid Dynamics Update" Webinars, it seems all they talk about is FLUENT, and CFX hardly gets mentioned.
I also heard of the Unified code about a year ago, and was kind of expecting it for the 15.0 release, but nothing yet.

[brunoc]

From what I heard a couple of years ago, a preview/first version should have been released with R15, but as we know, it wasn't.

R16, maybe? It will still be (kind of) within your 5 year range, Glenn.

[Lance]

Many years ago I heard v14 would have a unified solver, then it became v15, then v16, and so on... apparently a working name was (is?) FLUX (FLUent+cfX)

But I wonder if we will ever see it.

[S_teph_2000]

Got an e-mail from an ANSYS representative today. He's saying that a beta of a CFX/FLUENT unified code MIGHT BE available with the release of 16.0...They have to keep the dream alive right?!

Stephane

[Antanas]

I've heard that ANSYS is working on unified CFD code now, but it won't appear even in 16 release. Also I heard that head of CFD line is fluent-guy, therefore fluent gets more attention.

[JuPa]

I'd also like to see Ansys Meshing and ICEM merge.

I'd love the ease of use of Meshing, combined with the power of ICEM.

I know you can do something similar by going into meshing, create a new method and select "External ICEM solver" or something along those lines. However in my experience it's quite buggy. I want one unified meshing program.

[bmahnic]

I think that one of the differences are chemical reactions (combustion, etc.) which can be solved in the FLUENT solver.

[ghorrocks]

CFX can model chemical reactions. I have not done a detailed comparison of reactions both of them can solve, but I suspect they can both handle most reactions you are likely to come across.

[JuPa]

Originally Posted by ghorrocks

I had a discussion with an ANSYS senior developer in 2009 where I vividly recall him stating that if ANSYS has not released a unified CFD code within 5 years they have failed. They have 8 months left and the signs are not looking good .

Seems like they're going to fail.

[hpvd]

since there are even for Ansys v16 two completely independent "What's new guides" for fluent and cfx,
the "united version" of both to Ansys CFD seems to be in the far future...
or will it never happen??

find by google:

cfx:
http://dl.ptecgroup.ir/virtual_educa..._Tools_R16.pdf

fluent:
http://dl.ptecgroup.ir/virtual_educa...Fluent_R16.pdf

[brunoc]

Those exist for every software in the ANSYS portfolio. There is also one for Polyflow (another ANSYS CFD tool), and different ones for ANSYS Mechanical and ANSYS APDL (former ANSYS Classical), even though both are based on the same solver.

[brunoc]

BTW, even if/when a combined tool is announced, they can't just discontinue CFX and/or FLUENT, since a LOT of customers depend on them, many of which have custom tools built around those software.

You should expect CFX and FLUENT to keep going (and being supported/enhanced) for many years, even if this new thing is coming.

[hpvd]

Originally Posted by brunoc

BTW, even if/when a combined tool is announced, they can't just discontinue CFX and/or FLUENT, since a LOT of customers depend on them, many of which have custom tools built around those software.

yes exactly -this is the point.
When starting to build some new "software environment/addons" today -which tool to choose if both would meet the requirements?
When educating people in cfd software usage which one to use?
etc. ...
Announcing something like a rough roadmap/timeline for this topic would be helpful...

[brunoc]

Regarding building tools, my guess is that talking to ANSYS would be the best choice.

But on education, any CFD tool should do. If the person that is learning understands what the software is doing behind the curtains (equations being solved, what the models do, what the solver settings mean) they will be able to use any CFD application available.

[S_teph_2000]

Have you seen the Ansys Customer Portal lately. In the "Online Documentation" for Ansys 16, in the Fluid "Dynamic" Section there is no more "CFX" section; only "Fluent" and "CFD-Post"...Is it just an omission? did they really merge both applications???? the suspense is unbearable!!!!

Edit:

Ok, nothing to get excited about. I just checked the "Product variable Table" for ansys 16, and nothing is changed: same old licenses, same old CFX on one side and Fluent on the other...

[hmasenger]

Originally Posted by cdegroot

By coupled (more accurately I should say "fully-coupled"), I mean they are solved in the same matrix system simultaneously. The other option is called "segregated", meaning you solve one thing and then the other and iterate back and forth to convergence. For velocity and pressure an example of a segregated method is SIMPLE, where you solve pressure and velocity in separate steps and have some method for adjusting in between to conserve mass. A fully-coupled method solves for velocity and pressure in a single step.

The advantage of fully-coupled method is that it will generally converge in fewer iterations, although each iteration will take longer. For problems that don't like to converge it can be helpful to use a fully-coupled method since it is less likely to blow up. Since multiphase problems are notoriously difficult to converge it is helpful that CFX can solve the volume fractions coupled (I don't think Fluent has this; could be wrong though).

.

very useful comment .special tnx to Chris DeGroot

[pmechz]

I am simulating mixing of two fluids ( both of them are water with identical physical properties) in a 3D T-shaped micromixer. which software do you recommend for this simulation (CFX or Fluent)?

Best regard

[pmechz]

I am simulating mixing of two fluids ( both of them are water with identical physical properties) in a 3D T-shaped micromixer. which software do you recommend for this simulation (CFX or Fluent)?

Best regard

[ghorrocks]

Which ever one you are most familiar with. Both software can do this sort of simulation, so choose the one you prefer to use.

The most important thing is to use the software correctly and validate and verify thoroughly. Which software you use is of secondary importance.

[wchknudt]

Originally Posted by cdegroot

In my opinion, CFX is more user friendly, although Fluent users tend to debate that

Fluent uses a classical finite volume method and has many options for PV coupling (segregated and coupled). CFX uses the control volume finite element method is only a coupled solver. They have similar models implemented and probably similar accuracy overall. I've heard Fluent is a bit faster on average.

CFX is particularly good for turbomachinery and stiff multiphase problems since it can solve the volume fractions coupled. And the general grid interfaces are very useful.

I'm a newbie to CFD. May I ask what is PV coupling? Thanks!