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Fire Dynamics Simulator
https://pages.nist.gov/fds-smv/
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PROF output quantity has limited functionality #9060

Open shostikk opened 3 years ago

shostikk commented 3 years ago

PROF outputs could be used for many more quantities than solid temperature and solid mass fractions or density. Extending the usability, however, requires changing the QUANTITY labels to be consistent with other outputs, and using MATL_ID instead of QUANTITY='WOOD' type of inputs. For gas concentrations, I would add SPEC_ID.

This way, READ_PROF could call GET_QUANTITY_INDEX, like other read routines.

Any objections?

rmcdermo commented 3 years ago

Sounds good to me.

shostikk commented 3 years ago

Working on it. Few issues on the way:

rmcdermo commented 3 years ago

RHO_ZZ(N) is the QUANTITY='DENSITY', for SPEC_ID='whatever N is'. For example, SPEC_ID='SOOT' or 'METHANE'.

For 3D, the solid uses MALT_ID for the solid density and SPEC_ID for the gas density. I think that should work for 1D as well.

drjfloyd commented 3 years ago

Have DENSITY, SOLID DENSITY and GAS DENSITY? Then MATL_ID and SPEC_ID can limit the outputs to just that material or species.

rmcdermo commented 3 years ago

The way things are set up right now for 3D, we output using GAS_PHASE_OUTPUT the QUANTITY='SOLID CELL DENSITY'. This takes a MATL_ID. If none is given, then the total solid cell density if reported.

shostikk commented 3 years ago

Would it be clearer to use 'SOLID DENSITY' in all outputs, whenever referring to solid (a MATL or all MATLs)? DENSITY alone could always mean gas.

drjfloyd commented 3 years ago

If we want to have combined solid and gas, all gas, all solid, or any one of a solid or gas I think we need three QUANTITIES.

shostikk commented 3 years ago

Maybe providing gas (total or single SPEC) and solid (total or single MATL) would be enough at this point?

rmcdermo commented 3 years ago

The main confusion for me with "SOLID DENSITY" is that the density rho_s(n) for component n does not change. The "SOLID CELL DENSITY" is the "bulk density" in the 3D solver. I think it is important to distinguish between the material density and the bulk density of a cell (whether that is a 1D cell or a 3D cell). I am not wed to any particular notation. But 'DENSITY' and 'SOLID DENSITY' for MATL_ID are both ambiguous to me because I don't know if this is a point density or a bulk density.

I think we need to have it so that we have MASS in the cell = (RHO_S+RHO_G)*VOLUME of the cell. Both these densities are point densities integrated over the volume.

I'm kinda with Jason, that more QUANTITY options is fine. We can describe them well in the guides and know what we are getting.

rmcdermo commented 3 years ago

OK, actually, you see how confused this makes me... what I wrote above can be confusing---it is only correct for RHO_S and RHO_G as "bulk density". So, need also the case where MASS = (RHO_S VOL_S + RHO_G VOL_G) where VOL_S + VOL_G = VOL_CELL

shostikk commented 1 year ago

This issue is still on hold, waiting for gas transfer implementation, but kept so we remember the need