looking for a smart interface matlab fluent
 

Hey,

I just started to use fluent. To encounter a diffusion/permeation problem an udf has been written. Now I would like to know wether it is possible to use an interface with which data can be exported to be used in matlab. once these are optimised they should be able to be reimported in fluent for the next simulation. Is there any possiblity of a matlab fluent interchanging interface?

Hi chary,

I see that your question stayed unanswered for years...

Just in case you are still interested you can use Fluent aaS (as a Server). It is available on Fluent versions starting Release 14.

See my blog on http://www.ansys-blog.com/tag/matlab/ for more information and a sample of Matlab coding.


Sorin

Hi Sorin,
I am interested in the data exchange between fluent and matlab. I have got the pressure data from fluent and write a code to calculate it in matlab. Now my problem is how to import the data in matlab to fluent??
Thank you so much

Hi Wang

I will need more information to help but I will just make some assumptions, for simplicity of the blog post:

Assumption 1: Matlab is running on a Windows 64 bits machine
Assumption 2: Fluent is running on the same machine or on a network accessible remote machine
Assumption 3: Fluent version is R14.5
Assumption 4: You have a resonable understanding of Fluent UDFs, rpvars or parameters
Assumption 5: you have administrative rights on the Matlab machine
Assumption 6: Fluent client (no license required) is installed on the Matlab machine

Let me know if your specific case is different.

Step1: Modify your Fluent case such that all entities that you want in Matlab are mapped to Fluent rpvars or Fluent parameters
- rpvars are requiring a little bit more advanced Fluent skills, but they have the benefit that they can be used on both a UDF running on the Fluent machine and Matlab running on the Matlab machine
- parameters are easier to use and more stable. They are accesible in Fluent GUI and Matlab but not in the UDF (unless you map one to an rpvar)
Step2: start Fluent on Fluent machine in server mode. Do not start a journal (-i option) because you will do the journaling from Matlab. To start fluent in server mode you will have to add in the command line the -aas option.
For example instead of running "fluent 3ddp" you will execute "fluent 3ddp -aas".
Step3: collect the Fluent session key from the Fluent machine and transfer it to the Matlab machine. the Fluent session key is stored in a file called aaS_FluentId.txt
Step4: make sure that the Fluent client is registered on the Matlab machine
You will have to run a command like the following:
regsvr32 "C:/Program Files/ANSYS Inc/v145/fluent/fluent14.5.0/addons/corba/win64/COMCoFluentUnit.dll"

Step5:Start Matlab
Step6:Connect Matlab to Fluent. You will have to run a Matlab script like the following:
fluent = actxserver(‘ANSYS.CoFluentUnit.1′);
tui=fluent.getSchemeControllerInstance();
fid=fopen(‘aaS_FluentId.txt’,'r’)
fluentkey=fscanf(fid,’%s’)
fclose(fid)
fluent.ConnectToServer (fluentkey)
Step7: Execute you Matlab-Fluent program.

You have two Matlab objects (fluent and tui) that you can use drive Fluent.

If you want to do Fluent journaling from matlab, you can use
tui.DoMenuCommand(tuiCommand)
this will have Fluent execute the tuiCommand with no return
tui.DoMenuCommandToString(tuiCommand)
this will have Fluent execute the tuiCommand and return the output
tuiCommand is pretty much any valid command that you put in a Fluent journal file
Example:
tui.DoMenuCommand('solve iterate 10')
report=tui.DoMenuCommandToString('report summary no')

If you want to set or get the value of a rpvar, you can use
tui.GetRpVar(rpvarName)
this will have Fluent returning the value of the rpvar
tui.SetRpVar(rpvarName,stringifiedRpVarValue)
this will have Fluent set the value of a rpvar
Example
valuePressureRelax=tui.GetRpVar('pressure/relax')
tui.GetRpVar('pressure/relax','0.5')
If you want to set or get the value of a parameter, you can use
fluent.GetOutputParameterValueByname(parameterName )
this will have Fluent returning the value of the parameter
tui.SetInputParameterValueByName(parameterName,par ameterValue)
this will have Fluent set the value of a parameter
Example
valueAvgTemperature=fluent.GetOutputParameterValue ByName('avgtemperature')
fluent.SetInputParameterValueByName('massflowrate' ,0.5)
Of course you will need to have an output parameter called 'avgtemperature' and an input parameter called 'massflowrate' previously configured in the Fluent case.

Please let me know if this post was helpful to you. If you give me your e-mail, I will contact you.

I tried my best to have the code examples syntactically correct, but there might be some typos. You can refer to Fluent documentation or you can mention the issue to me and I will figure it out.

Thank you

Sorin

How about Linux?
 

Hi Sorin!
does this work on a Linux-mashine as well?
Thank You

Yes,

Yes, this works on Linux as well. The Matlab code and the set-up are slightly different though and problem specific.

I will contact you in private since this might require specific information about your environment.

Then I will try to provide a generic example of Matlab to Fluent cosimulation on a Linux environment on this blog.

Thank you

Sorin

Progress in using Fluent as a Server on Linux?
 

Hi Sorin
Did you make any progress using aas with Linux?

As obvious I couldn't find a dll in the Linux installation folder :-)).

So I think I have to compile the idl file myself, but I do not know which compiler should be used to drive Fluent-aas from Matlab.

In my System:

Matlab is running on a Linux 64 bit machine.
Fluent is running on a 64 bit network accessible remote machine.
Fluent Version is 15.0

Thanks for youre help in advance.

Dominik

Help
 

Hi sorin.

I have done all instruction but when Matlab wants to run tui.DoMenuCommand I have an error.

Error using
Interface.COMCoFluentUnit_1.1_Type_Library.ICoFlue ntSchemeController/DoMenuCommand
Invoke Error, Dispatch Exception: Unspecified error



Error in second (line 9)
tui.DoMenuCommand('aaS.pause');


I don't know what should I do?

Hi Sorin

Do you have any idea in writing a subroutine in connecting TRNSYS and Fluent for data exchange

Thanks in advance

Hi itsme_kit
I saw you posted this long time ago. If you solved this problem, could you please share some useful materials about how to connect TRNSYS and fluent? Or could you provide the procedures for realizing this coupling? Thanks in advance.

Hello Sorin and other CFD people,

Thank you for the nice guidelines provided for the Fluent-Matlab coupling.

Is it possible to change the material properties of a combustible particle remotely from Matlab? For example a devolatilization model called the Two-Competing-Rates, which I'd like to adjust with matlab, has multiple input values that have to be given by the user.

The figure below the shows the panel in Fluent. The values have to be directly provided by the user in the GUI so is there any way to remotely change these in Matlab?

Hi
my email id is ravi_12186@yahoo.co.in..I need a help regarding linking between fluent and matlab. It'll be very helpful if u can do that.
Thanks is advance

Thank you so much Sorin,

Because of your illustration here, I made a progress in my program.
Here, I just want to ask a question about execute-on-demand.

I have a interpreted UDF(DEFINE_ON_DEMAND), the name is readData. When I try to execute it from MATLAB code, it gives me an error:
Error: eval: unbound variable
Error Object: read_porosity

The code I wrote is :
tui.DoMenuCommand('define user-defined execute-on-demand "readData" ')

Can you help me to solve this problem.
Thank you in advance.

SHEN

Hi Shen,

I think that you just need escape the special characters in your command.

Try using
tui.DoMenuCommand('define user-defined execute-on-demand \"readData\"')

instead of
tui.DoMenuCommand('define user-defined execute-on-demand "readData" ')

Regards

Sorin

Hi ras1981,

That specific example would work if connecting Windows-Matlab with Linux-Fluent. the limitation is simply mainly due to the fact that the aaS connection is using actxserver, a Matlab command available on Windows only.

That approach is not anymore the ANSYS preferred way to access an ANSYS solver from Matlab.

There is a more efficient way to access Fluent and/or ANSYS Mechanical APDL running on all ANSYS supported platforms (Windows/Linux) from Matlab running on any Matlab supported platforms.

Please read my blog at http://www.ansys-blog.com/how-to-mak...ys/#more-15509

You will need download a Matlab "helper" from support.ansys.com. It is free but you must have an account on that website.

Sorry for the late reply

Sorin

Thank you so much, Sorin.

Hopefully that I can meet you here.
Thank you again.

SHEN:cool:

Thank you so much, Sorin.

Hopefully that I can meet you here.
Thank you again.

SHEN:cool:

Hello Sorin,

By the way, can i ask you to correct these two commands:

tui.DoMenuCommand('solve initialize compute-defaults all-zones')

tui.DoMenuCommand('solve initialize compute-defaults velocity-inlet inlet') or tui.DoMenuCommand('solve initialize compute-defaults velocity-inlet 9')

;););)

SHEN

Hi Shen,

The commands seem to be syntactically correct, but they might be invalid depending on the status of Fluent. I would recommend trying to type the commands on Fluent.

Even better, you can catch the exceptions from Fluent and read the content. Follow the instructions in my recent blog:
http://www.ansys-blog.com/ansys-fluent-matlab-example/

I had to use
in Matlab with ANSYS 18.