ensim.core.propellants#
Propellants in their storage state, with the reactant enthalpies NASA CEA uses.
PROPELLANTS maps each key to a Propellant; FUELS and OXIDIZERS list the
keys by role, in the order the desktop application shows them, and
LEGACY_NAMES maps the gas-phase names used by EnSim 3.x (H2, O2, RP1, …)
to the current keys.
| Key | Name | Role | Formula | T, K | h, kJ/kg |
|---|---|---|---|---|---|
| LH2 | Liquid hydrogen | fuel | H2 | 20.27 | −4470.5 |
| LCH4 | Liquid methane | fuel | CH4 | 111.64 | −5562.3 |
| RP-1 | RP-1 kerosene | fuel | CH1.9423 | 298.15 | −1768.6 |
| N2H4 | Hydrazine | fuel | N2H4 | 298.15 | +1572.2 |
| MMH | Monomethylhydrazine | fuel | CH6N2 | 298.15 | +1176.4 |
| UDMH | Unsymmetrical dimethylhydrazine | fuel | C2H8N2 | 298.15 | +813.7 |
| ETHANOL | Ethanol | fuel | C2H6O | 298.15 | −6023.9 |
| LOX | Liquid oxygen | oxidizer | O2 | 90.17 | −405.6 |
| NTO | Nitrogen tetroxide | oxidizer | N2O4 | 298.15 | −190.7 |
| HTP | Hydrogen peroxide (100 %) | oxidizer | H2O2 | 298.15 | −5520.6 |
| N2O | Nitrous oxide (vapour) | oxidizer | N2O | 298.15 | +1854.0 |
Propellants as they are loaded into a vehicle.
A liquid propellant enters the chamber with the enthalpy of the liquid at its storage temperature, not that of the gas at 298 K. For liquid hydrogen and oxygen the difference is several percent of chamber temperature, so reactants carry an assigned enthalpy, the same convention NASA CEA uses for its reactant list.
Enthalpies are mass-specific (J/kg) and come from the reactant entries of the
NASA Glenn thermodynamic database distributed with CEA 3.3.2 (McBride, Zehe &
Gordon, NASA/TP-2002-211556); scripts/generate_cea_references.py reproduces
them.