******************* This email originates from outside Imperial. Do not click on links and attachments unless you recognise the sender. If you trust the sender, add them to your safe senders list https://spam.ic.ac.uk/SpamConsole/Senders.aspx to disable email stamping for this address. ******************* Dear Nektar++, I am using the FieldConvert filter in my session file to output vorticity. I then isolate regions of my domain using the range option (-r) of FieldConvert in post-processing. To enable the isolation of these regions, I have found that I should produce .fld files with my filter as opposed to .plt, .dat, etc. Here is my filter: <FILTER TYPE="FieldConvert"> <PARAM NAME="OutputFile">Fields.vtu</PARAM> <PARAM NAME="OutputFrequency">1</PARAM> <PARAM NAME="Modules">vorticity</PARAM> </FILTER> When running in parallel, this filter will output .fld directories with .fld files in them each corresponding to the processors used. This is where the issue arises: I am running simulations on a cluster using many processors and I need to save lots of time steps. My cluster has a 1 million file limit, and I will quickly hit this if I do not convert and overwrite the .fld directories into single .fld files in-situ. I know the command to do this in post-processing: FieldConvert -f session.xml Fields_#_fc.fld/ Fields_#_fc.fld but so far, have not been successful in implementing this in-situ. I would be very grateful if you could offer a solution or at least steer me in the right direction with this issue. Thank you very much in advance, and I look forward to hearing from you. Sincerely, Isaac