Visualisation of agents moving in the smoke

[chraibi]

Hi,
I was wondering, if there is a way for smokeview to visualise agents moving in smoke.
I know FDS-Evac does not exist anymore, but I'm exploring some models, where pedestrians move in a room and interact with smoke in FDS-Evac style.

I can visualise the pedestrians with my tool. The smoke with smokeview. But it would be cool to do both, in smokeview.

With this discussion I just want to know:

• Is there something existing to do what I just described?
• if not, how 'easy' would it be to do it in smokeview? @gforney

[johodges]

Is the data format of your agent simulations supported by Paraview? If so you could load both the FDS and agent simulation results there for simultaneous comparison.

[drjfloyd]

A bit of hack but another possible approach is make a copy of your fds input file and change the CHID so you don't overwrite your prior simulation. Add a particle class to represent people. You can make particles look like cylinders so you could define for example a 2 m tall, 30-40 cm diameter cylinder particle. Run for a very short time. Then compare the two smokeview files. Some new stuff will be in the new smokeview file for the particle class (the defintion information and the output files). You could then make a copy of your old smokeview file (give the copy a new name) and add in the new particle stuff. Then have your pedestrian tool output particle data files using the format in the User's Guide. Run smokeview using the new combined file and load the particle output.

[chraibi]

hmm, very hacky indeed.
what if I write my trajectories as ptr5 files? would smokeview pick them up?
I once wrote a parser https://github.com/chraibi/prt5parser and now could do the inverse if this would solve my issue.

[drjfloyd]

Smokeview only knows the prt5 files exist if the appropriate particle related information is in the smv file. That is the reason for the steps of making an new FDS input file and merging the old and new smokeview files. But assuming you correctly add that information to the smv file as well as correctly format the prt5 files, then yes smokeview would pick them up.

[drjfloyd]

A related hack if you have problems with the first is you could use INIT and PATH_RAMP. Again a new fds input with a particle defined for people. Give it zero drag, emissivity, and heat transfer coefficient so it has no effect on the fluid simulation. Have your tool write an INIT with PATH_RAMP data for each person to a text file and CATF that in to the new FDS file. You would then need to run the entire simulation again. FDS would then write the particle data files where the particle position is defined using all the PATH_RAMP inputs.

[chraibi]

I think I will go with your first suggestion.
The second, if I understand correctly, requires a full FDS rerun every time agents move.

[rmcdermo]

I was just going to say what Jason said.... Sorry, not DEVC, INIT. Here is an example:

fds/Verification/Miscellanesou/part_path_ramp_jog.fds

Another example is:

fds/Verification/Species/FED_moving.fds

[chraibi]

Following up:
I implemented @drjfloyd's suggestion (write .prt5 + register it in the .smv) and it works. Summary:

1. Write a .prt5 file with agent trajectories
2. Patch the .smv by appending a CLASS_OF_PARTICLES block followed by a PRT5 block that references it

Thanks for the pointers!

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