How to extract SOOT DENSITY from SMOKE3D (.s3d) files in FDS 6.9.1? #15260
Description
I'm working with FDS 6.9.1 simulation output and need to extract soot density data for post-processing. Here's my situation:
Simulation Setup:
FDS version: 6.9.1
DUMP settings: SMOKE3D=.TRUE., DT_SMOKE3D=10.0
REAC settings: SOOT_YIELD=0.05
12 meshes, 3600s simulation time
What I have:
.s3d files (36 files, varying from 600KB to 9.5MB)
.q files (PLOT3D format with temperature and velocity)
Smokeview confirms SOOT DENSITY exists (shows "SOOT DENSITY: 75.8 MB" when loading 3D smoke files)
What I need:
I want to extract the 3D soot density data from .s3d files to combine with temperature data from .q files for quantitative analysis. The goal is to get x,y,z coordinates with corresponding soot density values.
Questions:
What is the correct way to read/parse .s3d files programmatically (Python preferred)?
Is there an official FDS utility to convert .s3d to ASCII/CSV/NetCDF format?
Are there any documentation or examples for the .s3d binary format structure?
Would fds2ascii work for .s3d files, or is it only for other formats?
What I've tried:
Attempted to read .s3d as Fortran unformatted binary (similar to .q files) but the format appears different
The data seems compressed (repetitive ff fe patterns in hex dump)
Any guidance on extracting soot density data would be greatly appreciated. Thank you!
Environment:
OS: Windows
FDS: 6.9.1-0-g889da6a-release
Compiler: Intel Fortran 2021.9.0