Extracting Particles

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mhoecker
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Joined: June 14th, 2021, 9:00 am
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Extracting Particles

Post by mhoecker »

Is there a way to convert the binary particle file (PARDUMP) into a format that can be read for post processing (ASCII, or netcdf, or ...). When extracted does that file include particles that have settled? If so does that include the time and location they settle?
alicec
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Re: Extracting Particles

Post by alicec »

There is a utility called par2asc which will convert PARDUMP output to ascii files. You can find it in the exec directory.

Description of the pardump/parinit file is here.
https://www.ready.noaa.gov/hysplitusersguide/S442.htm

There is python code with a class that can read/write pardump files here in pardump.py.
It returns a pandas DataFrame.
https://github.com/noaa-oar-arl/monetio ... tio/models

"Settled" particles will generally not be removed from simulation unless ICHEM=5 is used.
Please see 'deposition and decay" section here.
https://www.ready.noaa.gov/hysplitusers ... deposition
Also tutorial section:
https://www.ready.noaa.gov/documents/Tu ... _dryp.html

If particles are removed from simulation then their position is no longer written to the PARDUMP file.
mhoecker
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Re: Extracting Particles

Post by mhoecker »

Can you dump particles more often than 1/hr?
Fantine
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Joined: November 8th, 2012, 3:41 pm

Re: Extracting Particles

Post by Fantine »

If you set ndump < 0, particle positions will be written at each time step.
https://www.ready.noaa.gov/hysplitusersguide/S627.htm
For example, you will get PARDUMP in every minute if you set the time step to 1 minute (delt=1) and ndump=-1 for your run.
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