serial/parallel problem in force saving convergence history

behest · August 22, 2013, 07:44

Hi all,
I want to simulate a 3D wing, Low Reynolds, and transient flow by Fluent 14. It is very important for me that lift and drag convergence histories would be saved. The problem is when I use parallel processor, the files will be overwritten and the last time step result will be just saved and replaced; versus, using the serial in the processing options, the files will be written correctly and convergence history is obtained very good.
Has anybody had the same problem? How did you solve it?
Would anyone like to make a comment to solve the problem? Actually, I need to parallel several processor and achieve convergence history too.

behest · August 28, 2013, 08:35

Hello my friends
I could not solve the problem. Has anybody had any experience with this problem?
The problem is about different trends in the using of serial and parallel processor. In the parallel, lift and drag convergence history files will be overwritten

star · August 31, 2013, 08:31

Hi Ali. I am having the same problem of history overwriting in parallel solver. Have you found solution yet? Thanks

behest · August 31, 2013, 09:34

Hi my friend
Unfortunately, I have not found the solution yet.
Please inform me if you find the way to solve it.
May I ask you about your software version? Ansys fluent 14 or 14.5 or others? Do you simulate in 3D-transient flow too?

Quote:

Originally Posted by star

Hi Ali. I am having the same problem of history overwriting in parallel solver. Have you found solution yet? Thanks

HWei · August 31, 2013, 10:53

Quote:

Originally Posted by behest

Hi my friend
Unfortunately, I have not found the solution yet.
Please inform me if you find the way to solve it.
May I ask you about your software version? Ansys fluent 14 or 14.5 or others? Do you simulate in 3D-transient flow too?

Hi behest,

I got the same problem that comes to you.
My condition is 2D aerofoil, High Re, transient, DDES.
It works on me by serial as well to output the lift/drag Coefficient by time, but failed on parallel. It was the overwritten problem.
What I thought is the problem results from the origin code of ANSYS/Fluent.
BTY, the ANSYS version of mine is 14.0.1.
Hope these information could help you.
If there is any progress on this problem, please tell me. I restart my case on serial to obtain the time-base variables. It was too slow!!!
Good luck.

star · August 31, 2013, 11:16

Yes, currently i am also using serial processing for transient flow. Mine version is Ansys 14.0. I guess this problem may with these version 14. Let's see if someone has solution..

behest · August 31, 2013, 11:19

Thank you very much for your information. Actually we have the same problem and my software version is 14.0.0
I think that this problem is due to the crack. It may be solved by installing another version, for example 14.5

Quote:

Originally Posted by HWei

Hi behest,

I got the same problem that comes to you.
My condition is 2D aerofoil, High Re, transient, DDES.
It works on me by serial as well to output the lift/drag Coefficient by time, but failed on parallel. It was the overwritten problem.
What I thought is the problem results from the origin code of ANSYS/Fluent.
BTY, the ANSYS version of mine is 14.0.1.
Hope these information could help you.
If there is any progress on this problem, please tell me. I restart my case on serial to obtain the time-base variables. It was too slow!!!
Good luck.

behest · September 1, 2013, 15:50

Hi all,
I have already installed another version of Ansys, 14.5.7. It seems that is the last one.
Unfortunately, the problem has not been solved yet.
Conclution:
-this problem is independed on the installing ansys version
-this problem is just for transient flow
-I used TUI too; but it was not usefull

please let me know your experiances

star · September 2, 2013, 03:20

Hi. Some of my friends are using fluent v6 versions (not in Ansys) and they have no such problem. so i think for Parallel processing one should go to lower versions.
Good luck

behest · September 2, 2013, 06:02

Hi, thank you very much for your suggestion.
Actually, I need the ansys version for my problem because old version does not have some options.
May I ask you do you have ansys fluent 14? Have you had any experiences with this problem in transient flow and parallel?

Quote:

Originally Posted by star

Hi. Some of my friends are using fluent v6 versions (not in Ansys) and they have no such problem. so i think for Parallel processing one should go to lower versions.
Good luck

star · September 2, 2013, 08:57

I am using Ansys 14.0.0 version. I started using Parallel processing for transient flow a few weeks ago and i found this problem. I tried to find solution but not found yet. Recently i am using serial processing for transient flow but it's slow.

armlic · July 22, 2014, 04:49

Hello guys..

Somehow I have the same problem, most of the times I try Parallel it fails with the Overflow error, and most of the cases work OK with Serial..

If someone knows why or the theory behind, welcomed!

Regards!

August 22, 2013, 07:44	serial/parallel problem in force saving convergence history	#1
behest Member Ali.E Join Date: Sep 2010 Location: Lisboa Posts: 83 Rep Power: 16	Hi all, I want to simulate a 3D wing, Low Reynolds, and transient flow by Fluent 14. It is very important for me that lift and drag convergence histories would be saved. The problem is when I use parallel processor, the files will be overwritten and the last time step result will be just saved and replaced; versus, using the serial in the processing options, the files will be written correctly and convergence history is obtained very good. Has anybody had the same problem? How did you solve it? Would anyone like to make a comment to solve the problem? Actually, I need to parallel several processor and achieve convergence history too. Last edited by behest; August 28, 2013 at 08:29.

September 1, 2013, 15:50	install new version of ansys	#8
behest Member Ali.E Join Date: Sep 2010 Location: Lisboa Posts: 83 Rep Power: 16	Hi all, I have already installed another version of Ansys, 14.5.7. It seems that is the last one. Unfortunately, the problem has not been solved yet. Conclution: -this problem is independed on the installing ansys version -this problem is just for transient flow -I used TUI too; but it was not usefull please let me know your experiances

Similar Threads
Thread	Thread Starter	Forum	Replies	Last Post
Submerged fin, Convergence problem	supermouniette	FLUENT	10	July 6, 2009 11:47
Convergence problem	suthichock	Main CFD Forum	27	May 11, 2009 08:05
problem saving drag convergence history	raheelrasool	FLUENT	3	April 20, 2009 10:04
Convergence problem for P1 & Energy	HP	FLUENT	5	May 21, 2005 16:01
convergence problem with SIMPLER	NURAY KAYAKOL	Main CFD Forum	1	February 24, 1999 14:43

August 28, 2013, 08:35		#2
behest Member Ali.E Join Date: Sep 2010 Location: Lisboa Posts: 83 Rep Power: 16	Hello my friends I could not solve the problem. Has anybody had any experience with this problem? The problem is about different trends in the using of serial and parallel processor. In the parallel, lift and drag convergence history files will be overwritten

August 31, 2013, 08:31		#3
star Member Harry Join Date: May 2013 Posts: 68 Rep Power: 13	Hi Ali. I am having the same problem of history overwriting in parallel solver. Have you found solution yet? Thanks

August 31, 2013, 11:16		#6
star Member Harry Join Date: May 2013 Posts: 68 Rep Power: 13	Yes, currently i am also using serial processing for transient flow. Mine version is Ansys 14.0. I guess this problem may with these version 14. Let's see if someone has solution..

September 2, 2013, 03:20		#9
star Member Harry Join Date: May 2013 Posts: 68 Rep Power: 13	Hi. Some of my friends are using fluent v6 versions (not in Ansys) and they have no such problem. so i think for Parallel processing one should go to lower versions. Good luck

September 2, 2013, 08:57		#11
star Member Harry Join Date: May 2013 Posts: 68 Rep Power: 13	I am using Ansys 14.0.0 version. I started using Parallel processing for transient flow a few weeks ago and i found this problem. I tried to find solution but not found yet. Recently i am using serial processing for transient flow but it's slow.

July 22, 2014, 04:49		#12
armlic New Member Join Date: Jul 2014 Location: BW, Germany Posts: 9 Rep Power: 12	Hello guys.. Somehow I have the same problem, most of the times I try Parallel it fails with the Overflow error, and most of the cases work OK with Serial.. If someone knows why or the theory behind, welcomed! Regards!