[tj1972]

Hello Everybody,

This is my first post on this forum.

Do you use ANSYS 17?

Reason asking this is that CFX solver in ANSYS 17 is unbelievably very slow.

When I'm saying "slow" means that even a very simple steady state task with couple hundred thousands mesh takes long (something an hour or so while same task on previous versions was taking something 10 minutes or so). Although, ANSYS claims in all promotional videos claims 10x. Of course I'm not expecting it to run 10 times faster, but it does not even runs the speed what, for example, v16 was (or earlier versions) running.

Does anyone experiencing the same problem?

It's a same computer, same windows, same HDD, everything is same including myself. I'm using ANSYS for years and never experienced something like this.

What's wrong?

Thanks

P.S. By the way meshing is relatively fast compared to previous versions.

[ghorrocks]

Check your virus checker is not crippling it. Also check you have enough memory, other users are hogging CPU time.

[tj1972]

Originally Posted by ghorrocks

Check your virus checker is not crippling it. Also check you have enough memory, other users are hogging CPU time.

Thank you for reply.

Tell me, please, what exactly to check with antivirus/firewall. I think I'm using something from Microsoft (forgot the name).

With memory no problem (if you mean amount of RAM).

Also, what exactly do you mean under "...other users are hogging CPU time..."?

Thanks

[ghorrocks]

When a task is running turn on the task manager (windows) or top (linux) and see what tasks are taking up CPU time and hard drive time. If the antivirus is causing a problem it should should be hogging the CPU or HD.

If the firewall is a problem then it will probably completely stop the simulation (not just slow it down). It will mean the solver cannot get a license, cannot access an executable or cannot access a remote compute node and that will just stop the simulation.

[Opaque]

If you already ran the case with the same settings on two different versions using the same machine (w/o other programs running), you could post the timing diagnostics at the end of the output file so others can see where the extra time is being used. Hopefully it is something obvious.

In addition, I am sure ANSYS CFX support personnel would like to have a look at your case.

[evcelica]

Someone at my workplace reported that Version 17 was "really slow" as well. I have not checked it out myself yet though.

[tj1972]

Originally Posted by evcelica

Someone at my workplace reported that Version 17 was "really slow" as well. I have not checked it out myself yet though.

Thank you Evcelica for reply.

Did you have any chance to look into details?

Whatever I do nothing helps.
May be there is something, somewhere, deep in the options/preferences/I don't know where... needs some check mark to be activated or removed...

I'm already sick with all these...

[evcelica]

I just installed 17 and ran an old CFX benchmark:
17.0 is the same speed as 16.1 according to my benchmark: (1% faster actually)
I was running 5 distributed nodes with 1 core each.

I have no clue what your problem could be?? It's a long shot, but:
Have you uninstalled and reinstalled ANSYS?
Are you using workbench, or CFX standalone? I use standalone.
Are you participating in the Product Improvement Program?
I didn't, but supposedly there was an issue with this that has been corrected by the service pack 2 update:


17.0 SP2:

This service pack has corrected an issue related to outgoing data for the ANSYS

Product Improvement Program (APIP).

[tj1972]

Originally Posted by evcelica

I just installed 17 and ran an old CFX benchmark:
17.0 is the same speed as 16.1 according to my benchmark: (1% faster actually)
I was running 5 distributed nodes with 1 core each.

I have no clue what your problem could be?? It's a long shot, but:
Have you uninstalled and reinstalled ANSYS?
Are you using workbench, or CFX standalone? I use standalone.
Are you participating in the Product Improvement Program?
I didn't, but supposedly there was an issue with this that has been corrected by the service pack 2 update:


17.0 SP2:

This service pack has corrected an issue related to outgoing data for the ANSYS

Product Improvement Program (APIP).

Thank you Evcelica for taking time for the test.

Hmm, Something really very strange indeed.

I was busy with some other stuff and got some time about 2 -3 days ago and just out of curiosity took one of the old tests for contra-rotating props (I have done that in v16 earlier) since it involves quite an aerodynamics in there.

So, the strange thing is that it did this test nearly in the same time as v16 done in those days back. Meaning is - it started working with the speed close to v16. Meshing was faster than in v16 (just re-meshed it with exactly the same settings as before from the beginning just to compare).

Pure Magic!

The only difference between the time I opened this thread and now is Windows - about a week ago (or so) it made something about 30 updates to itself.

Bad news is that now FLUENT (after all those updates) does not want to start. . Honestly, I don't care too much with FLUENT behavior but, seems to me, that "Houston has a problem" in ANSYS with this 10x "innovations".

I don't know what to think.

[mirghani]

Hi everyone

I have the same problem with ANSYS 17.0 release. am working with ANSYS Workbench 17.0 "Static Structural" downloaded it a week ago. for the same problem, same meshing and same analysis settings, the run time takes more than 1 hr for 17.0 release whereas in case of version 16.0 it takes about 15-20 mints most. what is happening and what about the 10x thing they are talking about. am considering returning to workbench 16.0.

Any suggestions will be highly appreciated
Thanks in advance.

[Roderick]

Well, I've been having the same problem. I'm actually using the 18.0 release, and sometimes the calculations run pretty slow: for a 2D analysis, 3000-elements-only mesh, it takes some minutes, whereas I was expecting it to take just a few seconds. And then, all of a sudden, running the same project, it worked pretty well. My suggestion is to reinstall your ANSYS and reinitialize your machine. I'm also sure that the thread creator has already solved his problem, but this post may help someone that searches for it and and end up here.

[Msvsraj]

Guys i have been using ICEM for the last couple weeks by now but all of a sudden ICEM is not responding to any command which include movement of cursor .i do have a lot of ram left for this application.it became very laggy and i was not able to do anything with ICEM
ANY suggestions on how to fix this
Things I've already tried
1.reinstalled ansys 19.2
2.imported my working again
3.tried with different model
all the above didn't change the behavior of my ICEM

[Gert-Jan]

ICEM is very different from CFX.
So, I would ask the ANSYS Meshing & Geometry forum. Not the CFX forum
There I would also tell if you use ICEM standalone or through Workbench.