Animation Error in Fluent
 

Hi Everyone,

I am simulating flow over a square cylinder in 3D and trying to create animations of the vortex field.

I am applying the animations through: Solve/Monitors/Animations.

However, when the simulation finishes and I try to playback the animation to write the mpeg, I get this error:

----------------------------------------
"mpeg_encode param1"

MPEG ENCODER STATS (1.5b)
------------------------
TIME STARTED: Wed Oct 14 16:45:48 2009
MACHINE: unknown
FIRST FILE: .\/velocity-magnitude-1_1_0000.ppm
LAST FILE: .\/velocity-magnitude-1_1_0199.ppm
PATTERN: i
GOP_SIZE: 12
SLICES PER FRAME: 1
RANGE: +/-8
PIXEL SEARCH: FULL
PSEARCH: EXHAUSTIVE
BSEARCH: CROSS2
QSCALE: 8 8 8
REFERENCE FRAME: ORIGINAL


Input file too small! (ÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿ ÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿ ÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿ ÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿ ÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿ ÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿ ÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿ ÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿ ÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿ ÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿÿ)
Removing frame files ... done.
--------------------------------------

The animation files are saved as .hmf extensions, so I am not sure why it is searching for .ppm extension.

I have run a previous simulation with the same parameters and properties, but no error occurred. If anyone can help with this error and why it occurs, it will be greatly appreciated.

Thanks.

Andrew

"hmf" files store the entire image (in all three dimensions) so that even after creating the animation, you can tilt/zoom and create a new view and then save the video file.

"ppm" files are 'frozen' image files. They are very small (almost 1000 times smaller file size than hmf). But once created, you cannot change the view.

Before creating the video, Fluent will convert your animation frames to ppm.

You can try this:
Open the "cxa" file in the folder that contains the animation details.
In that change the second line from "NAME: .\moviename" to "NAME: moviename". (Remove the dot and slash).
Save the file, exit & reopen Fluent. Do not read any case. Now read the new cxa file and try creating the mpeg file.

Thanks srjp,

This helps alot. I will try what you have suggested and let you know how it goes.

I notice that everytime Fluent is closed without creating the animation from the .hmf files, when Fluent is reopened, it does not allow the animation to be created and displays again another error message.

Can this be related to your suggestion, modifying the second line in the .cxa file?

Thanks again. I'll keep you posted on how it goes.

Regards

Andrew

Thanks Srjp. Your suggestion worked great! Really appreciated.

I was always deleting the hmf files after closing Fluent because it would not read the cxa file once reopening Fluent. I always ran the simulations again and tried to create the animation before closing Fluent.

When opening Fluent, I should ensure the cxa file has been modified?

Thanks again.

Andrew

Thats right.
For reasons I don't know, fluent changes the cxa file sometimes.
There is nothing wrong with the hmf files. Once you have created a set of hmf files and the linked cxa file, you don't need the case/data file at all. You just need to open fluent and then play/record your movie.

That's great! It is really good to know.

I notice that it does it more often when I have several animations being saved during the simulation. Maybe there is a memory requirement for Fluent. If the time step is too small or there are alot of .hmf files to read, Fluent tries to modify them to .ppm files, so it can read the animation.

It is good that the animations can be played and recorded just from the Fluent window and not by reading the case/data file.

Thanks for the help.

Andrew

Thank you srjp for the reply to Andrew, it was so elaborate and i also got helped on the way. I am using Fluent 12.1 and seems the handling is deferent from the Fluent 6.2 version. I am not getting errors when writing Mpeg.

Sorry i dont get it, i have the same probem. i have both cxa and hmf files but mpeg file is not created. gives an error of ppm file cannot be created. I dont get the suggestion of changing second line...pls help to clarify

your solution doesn't work for me. although its possible to play the sequences, writing as a mpeg or....is impossible. do you have any idea?

But how to open .cxa file ?
 

How to open that .cxa file again in Fluent ?
What is to be selected when reading it in Fluent ?
Is it a case, or the data, or something else ?
I really didn't get it.