RCAIDE.Library.Attributes.Propellants.Liquid_Natural_Gas

Liquid_Natural_Gas#

class Liquid_Natural_Gas(*args, **kwarg)[source]#

Bases: Propellant

A class representing Liquid Natural Gas (LNG) fuel properties and composition for propulsion applications.

tag#

Identifier for the propellant (‘Liquid_Natural_Gas’)

Type:

str

reactant#

Oxidizer used for combustion (‘O2’)

Type:

str

density#

Fuel density in kg/m³ (414.2)

Type:

float

specific_energy#

Lower heating value (LHV) specific energy content in J/kg (48.632e6)

Type:

float

energy_density#

Energy density in J/m³ (22200.0e6)

Type:

float

stoichiometric_fuel_air_ratio#

Stoichiometric fuel-to-air ratio [-] (0, placeholder)

Type:

float

heat_of_vaporization#

Heat of vaporization at standard conditions in J/kg (0, placeholder)

Type:

float

temperature#

Temperature of fuel in K (0, placeholder)

Type:

float

pressure#

Pressure of fuel in Pa (0, placeholder)

Type:

float

fuel_surrogate_S1#

Mole fractions of fuel surrogate species [-]

Type:

dict

kinetic_mechanism#

Kinetic mechanism name for fuel surrogate combustion

Type:

str

oxidizer#

Oxidizer species name

Type:

str

emission_indices#
Emission indices in kg/kg fuel
  • Productionfloat

    Upstream extraction and liquefaction CO2 (0.35)

  • CO2float

    Carbon dioxide (2.75)

  • COfloat

    Carbon monoxide (0.00100)

  • H2Ofloat

    Water vapor (2.20)

  • SO2float

    Sulfur dioxide (0.0)

  • NOxfloat

    Nitrogen oxides (0.0126)

  • Sootfloat

    Particulate matter (0.0)

Type:

Data

global_warming_potential_100#
100-year global warming potentials (CO2-equivalent per kg of species)
  • CO2float

    Carbon dioxide (1)

  • H2Ofloat

    Water vapor (0.06)

  • COfloat

    Carbon monoxide (1)

  • SO2float

    Sulfur dioxide (-226)

  • NOxfloat

    Nitrogen oxides (52)

  • Sootfloat

    Particulate matter (1166)

  • Contrailsfloat

    Contrail formation factor in kg CO2e/km (11)

Type:

Data

materials_properties#

Interpolated thermophysical property data loaded from LNG_properties.res

Type:

dict

Notes

LNG is a cryogenic fuel consisting primarily of methane with small amounts of heavier hydrocarbons. It requires storage at approximately -162°C (-111 K) but offers reduced carbon emissions compared to conventional jet fuels.

The specific_energy value uses the lower heating value (LHV) of LNG, which excludes the latent heat of water condensation in combustion products.

Definitions

‘Global Warming Potential (GWP-100)’

Relative measure of heat trapped in the atmosphere over 100 years compared to an equivalent mass of CO2

‘Energy Density’

Energy content per unit volume, dependent on cryogenic storage conditions

Major Assumptions

  • Properties are for saturated liquid at atmospheric pressure

  • Composition represents a typical LNG mixture

References

[1] Lower and Higher Heating Values of Gas, Liquid, and Solid Fuels.

NPRE 470 course resource, University of Illinois Urbana-Champaign, 2018. https://courses.grainger.illinois.edu/npre470/sp2018/web/Lower_and_Higher_Heating_Values_of_Gas_Liquid_and_Solid_Fuels.pdf

cryogen_properties(T, prop_name)[source]#

Return an interpolated LNG thermophysical property value at a given temperature.

Parameters:

  • T (float or ndarray) – Temperature(s) in Kelvin at which the property is requested.

  • prop_name (str) –

    Name of the property column to retrieve from the LNG data file. Valid keys include:

    • "Temperature (K)"

    • "Pressure (MPa)"

    • "Density (kg/m3)"

    • "Volume (m3/kg)"

    • "Internal Energy (kJ/kg)"

    • "Enthalpy (kJ/kg)"

    • "Entropy (J/g*K)"

    • "Cv (J/g*K)"

    • "Cp (J/g*K)"

    • "Sound Spd. (m/s)"

    • "Joule-Thomson (K/MPa)"

    • "Viscosity (Pa*s)"

    • "Therm. Cond. (W/m*K)"

    • "Phase"

Returns:

prop_value – Interpolated property value(s) corresponding to the input temperature(s).

Return type:

float or ndarray

Notes

  • Property data is loaded from LNG_properties.res via load_lng_properties().

  • Linear interpolation is applied between tabulated data points.

  • Extrapolation outside the tabulated temperature range is not supported (fill_value=None).

  • The "Phase" column is categorical and is not suitable for numerical interpolation.

See also

load_lng_properties

load_lng_properties()[source]#

Load liquid natural gas property data from the RES file.

Parameters:

None

Returns:

lng_data – Raw liquid natural gas property data loaded from LNG_properties.res.

Return type:

dict

Notes

Assumes liquid natural gas is pure Methane and behaves as an ideal fluid for the stored properties.

Source#

Internal RCAIDE resource file: LNG_properties.res

See also

RCAIDE.load

Function used to load RES files