BurnSim.Thermo
==============

This assembly implements chemical-equilibrium propellant analysis. Its solver and its
thermodynamic data are derived from NASA's CEA (Chemical Equilibrium with Applications),
used under the Apache License, Version 2.0.


Portions derived from NASA CEA
------------------------------

CEA - Chemical Equilibrium with Applications

Copyright (c) 2025, United States Government as represented by the Administrator of the
National Aeronautics and Space Administration

Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file
except in compliance with the License. You may obtain a copy of the License at

    http://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing, software distributed under the
License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND,
either express or implied. See the License for the specific language governing permissions
and limitations under the License.

What is derived:

  * The chemical-equilibrium solver and the rocket-performance driver are transliterated
    into C# from CEA's Fortran sources (equilibrium.f90, thermo.f90, rocket.f90).

  * The embedded species table (Data/species.inp.gz) is a subset of CEA's thermodynamic
    database, data/thermo.inp, filtered to species reachable from the elements that occur
    in solid rocket propellants. The record format and values are unmodified.

    Source/References for that database: NASA TP-2002-211556
    https://ntrs.nasa.gov/api/citations/20020085330/downloads/20020085330.pdf

  * Validation fixtures are compared against NASA RP-1311 example outputs distributed with
    CEA.

    Source/References: NASA RP-1311 Part 2
    https://ntrs.nasa.gov/api/citations/19960044559/downloads/19960044559.pdf


Not derived from PEP, ProPEP, or cpropep
----------------------------------------

No code or data from PEP, ProPEP, or cpropep is used here. Those implementations are
distributed under the GPL and are deliberately not a source for this work. Where BurnSim's
user interface describes this feature as "ProPEP-style", that is a statement about what the
feature resembles, not about its origin. Results are not expected to match ProPEP's exactly.
