Learning Forum

[nepomnyi]

Hello dear ANSYS community.

I simulated a transient water-air flow in a vertical 3-D pipe using ANSYS FLUENT 19.2 (Eulerian model). Using File --> data file quantities, I specified which flow parameters I wanted to be included into the results file - namely, I wanted cell volumes to be included.

After the simulation, was done I used File --> export --> data & case --> .h5 files to export the results in HDF5 format in order to process the results in Python.

But when I opened my HDF5 results file, I saw that cell volumes and other flow parameters which I specified were not included into my HDF5 results file. I am pretty sure though, that ANSYS included them into the standard .dat file which I can see in my ANSYS folder by can't obviously open in Python.

I want to export the results of my simulation in HDF5 format with all the flow parameters that I want.

I am wondering if anybody can help me with it please.

Thank you in advance.

Ivan

[Rob]

Try in 2019R3, the HDF5 format was fairly new then.  What do you need to do with the data?

[nepomnyi]

Ok, I see, thank you very much.

With regards to data processing - a lot of fancy things, including multivariate analysis - I am doing my Ph.D. If you are hinting at UDFs or ANSYS post processing tools - then no, just no. I recognize their abilities but I am not a fan of them, don't want to learn how to use them and, actually, I am trying to avoid playing more than necessary with ANSYS at all costs (I don't like at all its philosophy of interaction with users). To say nothing that considering the scale of my study - ANSYS post and pre processing tools might not be that helpful.

I recognize that ANSYS is a powerful tool and may be way ahead of the competitors and so on, but I just want to get my simulation results out of that thing and forget about it. The standard is HDF5 - it's a really good format. CGNS could've worked for me (they strive to be a standard format for CFD data storage) but for some reason CGNS files generated by ANSYS can't be read by any of the Python's HDF5 libraries. And Python's CGNS library is almost impossible to use. So for now, I ended up using plain text files to get my cell volumes ...

[Rob]

Have a look at User Defined Memory and interpolation files: can't explain more, but it'll give you some reading for the PhD. Also check the various Export options as I think CGNS is binary by default, if not try ASCII? 

I'd also suggest working out exactly what you want to do with all the data. Whilst the ANSYS tools may not do everything you want [need] you may be able to significantly simplify the next [external] steps by using some of the available functions. 

[nepomnyi]

Thank you, I'll check it and will give it a try.

Ivan

[ehkh]

Hi Nepomnyi / ansys team,I am exporting HDF5 transient data files from fluent 2020 R1, and trying to postprocess them in python but can't understand the files structure yet (my simulation is for a 3D trapezoidal geometry)nnCould you please provide further documentation on the Common Fluids Format (CFF) that is used to write the H5 files ,, also could you please provide me with documentation and resources that could help in reading the data in python.nI wanted to know also if exporting the node values rather than the cell values would be more convenient for this h5 files to be read in python?nThanks,nEsra'a n

[chen chen]

Hello, blogger, have you found a way to read the fluent dat file with python? My most research also needs to use python to read the node data (pressure, density, etc.) in the dat file

[Rob]

If it's not covered in the documentation I can't supply any information on the format. If you look in the File -Export menu there are other options, ASCII or similar may be easier to work with. n

[chen chen]

Hello, blogger, have you found a way to read the fluent dat file with python? My most research also needs to use python to read the node data (pressure, density, etc.) in the dat file