How to restart from past time step, data disappears
 

I would like to start my transient simulation from a given time step. I figured out that it works with File > Import > Data, but then all saved data of the time steps before disappear and I can't see the past results anymore. The files are even gone from the project folder. I save the data with autosave every time step (without saving the case file). Please help me, what am I doing wrong? How can I keep the data?

To store data you can use autosave (which you did) or manually
file ->write -> data
to read data use
file -> read -> data (not import)

I've never heard, that data files could disappear from working directory

There is no Read > Data. Under Read there is only Profile, Scheme and Journal and some greyed out options (PDF, ISAT Table, DTRM Rays, View Factors). None of the available options show the desired FFF...dat.gz files. I'm using Workbench 2019 R2.

???

And yes, they really disappear. First, they are moved to the backup folder and after saving, they are deleted. I tried to copy them back into the folder but the project cant read them any more. I even asked a programmer to manipulate the project file to read them but that only leads to several errors and there must be a better way.

Thank you for your reply!

Import
 

Some of the menus in Fluent change while used within WB. Options that usually appear in Read move to Import. As far as disappearance is concerned, that is the expected behavior if you start Fluent from setup cell. If the objective is to continue from a previous point, solution is to start from Solution cell.

No code is required to maintain files. Those can be easily copied anywhere. However, if procedure is followed correctly, this would not be required.

Hi melona. If the files disappear from the working directory, I would suggest to create a simple test case. I.e. flow in a pipe with constant velocity at inlet and outlet. Make it run as transient. Enable auto-save. If the auto-save results still disappear in this simple case, please post the .cas file here. --Svetlana

Hi Vinerm,
I know, I did start Fluent from Solution cell. I actually didn't even close the fluent window after calculation. But there is only the import option for data.


I guess the only way that's left is to just save the project in between and just close without saving when there is divergence. I'll loose some hours but the calculation takes weeks anyway. (Luckily I had a backup!)
Maybe it's a version bug or it's because it's an university license (not the student one, its a full version but not for commercial purpose)?



Can someone tell me if they actually have the File > Read > Data option in the Workbench 2019 R2 version?

Options in WB
 

Within WB, it will always be File > Import > Data. If there is no specific requirement to run the cases in WB, I'd recommend running all Fluent simulations outside WB. User does not have much control in WB.

How can I run it outside WB? Does that mean I have to create it with the old interface Mechanical ADPL? I can't open my WB project there.

Fsi?
 

Are you running an FSI problem? If that is the case, then you better use WB. If not, then Mechanical or APDL have got nothing to do with it. Just start Fluent from the terminal, if using Linux, or from Start Menu, if using Windows. Load the case file that would already be existing in WB directories and run the simulation. Then, you will also have option to read case and data files under File > Read and not under File > Import.

Okay, now I got it. It really works only within the fluent application outside workbench. Is there any way to import all of the results back into WB? I would love to work with the WB results cell.

Why didn't they implement it into WB??!!! :mad:

Thank you very much for your help!

Result Cell
 

Result Cell is nothing by CFDPost. You can start CFDPost also outside WB and load .dat(.gz) files from Fluent. You can also export CFDPost specific .cdat files from Fluent using File > Export. These files are much smaller in size.

Thank you! That works well!

For anyone facing the same hussle, thats what I figured out further:
In CFD-post its file > load results, then find the FFF > Fluent folder and choose the last generated .dat.gz file. It will load all previous time steps, too. But only if you used the Read option in the Fluent application (without using workbench) like written above. It doesn't work with pasted files. Somehow CFD-Post can't put the data together again after they onces got deleted due to importing.

Putting data together
 

CFDPost can put the data together only if the data file has list of previous files in it. If case quits in between, e.g., crashes due to divergence, the list is reset.