[biltu]

Hi CFDians,
I want to create/record a script to automate the repetitive steps in CFX pre and post. Could anyone tell me how will I be able to do so?

I recorded the script in the workbench which works fine but only for the workbench. This script does not record anything that I do in the Designer Modeler, Mesh or CFX pre and post.

Looking for help to automate steps in all or any amongst Designer Modeler, Mesh or CFX pre and post.

[Opaque]

Best to read the documentation.

The scripting language for ANSYS CFX is Perl plus CFX Command Language (CCL). You can record a session in CFX-Pre/CFD-Post and look at the session file to get an idea.

Using a recorded session as a template, you can insert your specifics.

[biltu]

Dear Opaque,
Thank you for your answer.
Where/How can I possibly record CFX pre & CFD post?
I am new to CFX.

[Opaque]

- Start CFX-Pre/CFD-Post
- Before you open any file, go to the Session top menu
- Select New Session
- Select Session/Start Recording
- Now start your work like
- Open the file,
- Load the mesh
- Setup some physics, or whatever you feel you want recorded
- Select Stop Recording

There should be some file named <your case>.cse file in your directory/folder.

You can edit that file, and read it through to understand how CFX-Pre works.

If you want to repeat the same steps in exactly the same order, you can close CFX-Pre (not quit), and now use Session/Play session and it should repeat whatever was recorded and you will be again exactly where you stopped recording.

[biltu]

Thank you Opaque.

It works more or less as I don't have exact same parts but only similar to one another. It saves a lot of manual work though.

Is it also possible to automate somehow in the mesher tab of CFX or the general mesh/geometry tab?

My model has ~30M elements. When I open CFX after meshing, it takes a ton of time to open/load the model in the CFX. I checked the amount of CPU and memory being used during loading file and found that only a fraction of available CPU and memory is being used. Is there any possibility to control the usage of available CPU and memory? OR use parallel computation for this step somehow? I have successfully used parallel computation for CFX solution and mesh generation.

[ghorrocks]

It sounds like your model is bigger than your RAM can handle so it is going to swap memory (or the page file, same thing). So this would accelerate greatly by increasing the RAM in your workstation. There are no CPU or memory settings you can adjust to fix this, you just need more memory.

[biltu]

Dear Ghorrocks,
I have 128GB RAM but only 10-15GB are being used when loading the model. I am wondering why the rest of 115 are sitting doing nothing? and if I can put this available resources for the task?

[ghorrocks]

It is the OS doing this, not CFX. When the memory required exceeds available physical memory it will start using the page/swap file to reduce memory useage, and this reduced useage is what is shown. If you want to control this look at the page/swap file settings on your PC - but use it carefully, you can brick your computer if you stuff it up.

Also don't forget that other applications take memory as well. So make sure you close other applications down. Even better, do the simulation straight after rebooting the computer.

This thread has good information if you want more detail: estimating RAM

[biltu]

Thank you ghorrocks. This issue is clear now.

I have one final question. Can I automate mesh generation? How?

[ghorrocks]

The easiest way to automate mesh generation is to run it inside workbench. Then you have a workflow you can run, parameters and all that.

If you want to drive the mesher directly yourself then your best bet is to go to ICEM or Fluent mesher. These can be run via scripts easily. ANSYS mesh looks horrible (or impossible) to run via a script.