CFD Online Discussion Forums

CFD Online Discussion Forums (
-   FLUENT (
-   -   OpenFOAM vs. Fluent & CFX (

marco February 29, 2008 17:57

OpenFOAM vs. Fluent & CFX
RANS modelling had its days and now LES is taking over. CFX is not a very good software for serious LES work. I am not so sure about Fluent. Considering the cost and limited features that CFX and Fluent offer, is it still worth to work on such softwares?

On the other hand OpenFOAM offers much more than CFX for both RANS and LES modelling and its absolutely free of charge. OpenFOAM results have proven to be much more accuarte than other commerical codes. When OpenFOAM is the future then why work on CFX and Fluent. Why are you guys still using CFX and Fluent and have you considered switching to OpenFOAM? Comment please

Carlos March 1, 2008 11:30

Re: OpenFOAM vs. Fluent & CFX
Hi Marco,

I have been using Fluent for 4 years now as part of an MSc in CFD and I am in the final stages of my PhD. For me Fluent is user friendly and it satisfies most of my needs. As for CFX, I know that this is better in some regards but I have never tried it long term so can't really make a comparison. Star-CD is supposed to be very good and is the industry standard for the likes of F1 teams, however I havn't tried that at all.

As for OpenFOAM I really do think it is just a matter of time before it takes over. Once I have finished my PhD I will be switching to this program because it does apparently have a lot to offer. Obviously a major plus is no license fee and these are astronomical for the commercial codes. I don't blame them, they produce bespoke software and they want a good price. One thing I DO know is that pretty soon, universities will get fed up with increasing CFD costs and the switch to open source codes will commence.

Currently, even the F1 teams are trying it out. I think the main reason why the switch hasn't happen much yet is that we are all so used to the likes of Fluent which has been around since 1988. There are 3 providers with most of the market share around the world and it must be said that when you do buy their sofware you also get technical support - this is something you have to pay for with OpenFOAM.

As an experienced CFD user I can usually work most things out but from time to time I NEED extra help. This forum is superb for that but sometimes nobody here can help and it is time to contact Fluent. Overall, I think that OpenFoam is definately the future and once there have been enough test cases showing a direct comparison between commercial Vs free software, we cannot be sure which is best.

One final comment is that the freeware meshing programs are not as advanced as the likes of ANSA and TGrid so this needs to be worked on. I would say give it 5 years and you might well see a full on war! The commercial company's will simply have to lower prices or offer something extra to keep customers. Of course they will be working night and day presently to do this but it will be interesting to see how things turn out. Personally, I hope OpenFOAM wins and provides what I consider a very important tool for mankind.


Jan March 1, 2008 13:31

Re: OpenFOAM vs. Fluent & CFX
I work with oil droplet combustion, is that available in Open Foam ? Last I checked it was not, so the reason why I do not use Open Foam - it has not the models I need.

marco March 1, 2008 15:09

Re: OpenFOAM vs. Fluent & CFX
Thank you Carlos for your insight into the subject. I am at very initial stages of my PhD, and i am looking into subject to decide which software i want to work with, thats why i posted this message here. I personally believe that OpenFOAM is the future at least for research community, so it is better to make a switch early than later. Moreover, when we look at comparative studies conducted between OpenFOAM and other commercial codes, OpenFOAM seems to produce better results. Although openFoam is more difficult to use and we do not get support that CFX or Fluent customers do, it will be better in the long term for a student like myself to stick with OpenFOAM.

what kind of models do you need to use jan for your work?

Carlos March 1, 2008 17:13

Re: OpenFOAM vs. Fluent & CFX
Marco, If you are starting a PhD you have the world at your feet! I would advise that you use open foam but maybe compare the performance of it and a commercial code for a few test cases. If open foam is better then you can justify using it for the rest of your PhD. I will be doing research after my PhD and i have already advised lecturers to get some students comparing the two code types. Eventually we would want students using openfoam for the reasons I mentioned earlier. Good luck with your studies,


BastiL March 2, 2008 16:45

Re: OpenFOAM vs. Fluent & CFX
Interesting discussion. From my eyes of view what OpenFOam can offer is a very good solver with lots of models and the option to modify the source code. His is an big advantag eover commercial codes. What commercial codes can over over support is a more or less closes process from CAD to Postprocessing. This is not the case for OpenFOAM. As mentioned, especially meshing is a problem. However this could be overcome with some commercial stand-alone mesher.

Aidan March 2, 2008 19:27

Re: OpenFOAM vs. Fluent & CFX
I used Fluent for my PhD and now work as a CFD engineering consultant. We use the Fluent code because it has a very broad range of models for all the industrial applications we model. Also, Fluent has excellent support which is very important when you work on large numbers of industrial problems.

However, if you are just starting your PhD then I would say OpenFOAM would probably be the better code for research. It gives you a lot of flexibility if you want to write some extra code for the solver. It can be difficult sometimes to implement complex user defined models in Fluent.

RE13 March 4, 2008 10:27

Re: OpenFOAM vs. Fluent & CFX
Does OpenFoam have multiphase solver?

keerthivasan March 18, 2013 09:05

Hi Marco,

I am now in my final year Under-Graduate engineering program & interested in learning multi-physics simulation software & very interested in Open-Source software.

I hope by now, you must have finished your Ph.D.

So, can I know how was your experience with OpenFOAM?
Also, any tips for a beninner like me.

KevinW August 18, 2013 02:30

hey, all.
I am in the first year of my master, and I wish to go for a phd.
I'm now playing around wind turbine with ANSYS CFX, but universities like DTU, Delft, NTUA, and NREL they seem to prefer developing in-house codes than commercial softwares. Is anybody familiar with this field, or maybe just some infomation on the trend of OpenFoam?

lenzo February 23, 2014 06:17

Hello there,
how is this question nowadays?
I am beggining in OpenFoam, but i would like to know whether it's the best product avaible.

Michael-STM February 25, 2014 16:56

Learning a CFD code and interacting with his GUI have a very shy learning curve. I'm also a begginer ad my suggestion is to try for yourself different codes since what is the "best" choice depends on what are your goals and your personality.
Also a basic requirement is reading a good theory starting guide (like the textbook from Anderson)...

drmarcoguevara December 6, 2014 15:21

i'm user of both
Hi Marco, i have been using fluent for two years now and fluent for a year, the two approaches are great. i peronaly like to use openFoam but in the office we have licence for Fluent that allow us to develope projects alittle bit faster and with less preprocessing and post processing time in therms of work time per engineer, i think this situation is gonna change in the future due to the benefits and interesting accuracy of free software, i personaly prefer the use of free source codes as openFoam and for my perosnal projects i use it, i hope my opinion to be usefull to yo if you want to talk about something else in detail write to me (

Bye Guys See you!:p:p:p:p;););):cool::cool:

lsiva93 February 18, 2015 00:19

Hi Carl,

I am an undergrad student in the final year and doing my project in CFD. I would also like to do my PG in CFD if possible. What is the scope of the career path?

And since it has been more than 5 years since you posted that message, do you think OpenFOAM has outrun ANSYS and other similar commercial software?

If so, will you recommend it to an undergrad?

All times are GMT -4. The time now is 09:08.