Rocket module#

In this section, you will find the documentation of the routines implemented to obtain the rocket propellant performance under ideal conditions. There are two models:

  • IAC: Infinite-Area-Chamber,

  • FAC: Finite-Area-Chamber.

Note

This module is based on Gordon, S., & McBride, B. J. (1994). NASA reference publication, 1311.


Routines
compute_chamber_FAC(self, mix1, varargin)#

Compute chemical equilibria at the injector, outlet of the chamber, using the Finite-Area-Chamber (FAC) model

This method is based on Gordon, S., & McBride, B. J. (1994). NASA reference publication, 1311.

Parameters:
  • self (struct) – Data of the mixture, conditions, and databases

  • mix1 (struct) – Properties of the initial mixture

Optional Args:
  • mix2_inj (struct): Properties of the mixture at the injector of the chamber (previous calculation)

  • mix2_c (struct): Properties of the mixture at the outlet of the chamber (previous calculation)

  • mix3 (struct): Properties of the mixture at the throat (previous calculation)

Returns:

mix2_inj (struct) – Properties of the mixture at the injector of the chamber mix2_c (struct): Properties of the mixture at the outlet of the chamber mix3 (struct): Properties of the mixture at the throat

compute_chamber_IAC(self, mix1, mix2)#

Compute chemical equilibria at the exit of the chamber (HP) using the Infinite-Area-Chamber (IAC) model

This method is based on Gordon, S., & McBride, B. J. (1994). NASA reference publication, 1311.

Parameters:
  • self (struct) – Data of the mixture, conditions, and databases

  • mix1 (struct) – Properties of the initial mixture

  • mix2 (struct) – Properties of the mixture at the outlet of the chamber (previous calculation)

Returns:

mix2 (struct) – Properties of the mixture at the outlet of the chamber

compute_chemical_equilibria(self, mix1, pP, mix2)#

Compute chemical equilibria for the 2 given thermodynamic states, e.g., enthalpy-pressure (HP)

Parameters:
  • self (struct) – Data of the mixture, conditions, and databases

  • mix1 (struct) – Properties of the initial mixture

  • pP (float) – Pressure [bar]

  • mix2 (struct) – Properties of the final mixture (previous calculation)

Returns:

mix2 (struct) – Properties of the final mixture

compute_exit(self, mix2, mix3, mix4, Aratio, varargin)#

Compute thermochemical composition for a given Aratio

This method is based on Gordon, S., & McBride, B. J. (1994). NASA reference publication, 1311.

Parameters:
  • self (struct) – Data of the mixture, conditions, and databases

  • mix2 (struct) – Properties of the mixture at the outlet of the chamber

  • mix3 (struct) – Properties of the mixture at the throat

  • mix4 (struct) – Properties of the mixture at the exit (previous calculation)

  • Aratio (struct) – Ratio area_exit / area_throat

Returns:

mix3 (struct) – Properties of the mixture at the throat

compute_rocket_parameters(mix2, mix3, gravity, varargin)#

Compute Rocket performance parameters at the throat

This method is based on Gordon, S., & McBride, B. J. (1994). NASA reference publication, 1311.

Parameters:
  • mix2 (struct) – Properties of the mixture at the outlet of the chamber

  • mix3 (struct) – Properties of the mixture at the throat

  • gravity (float) – Gravitational acceleration [m/s2]

Returns:

mix3 (struct) – Properties of the mixture at the throat

compute_throat_IAC(self, mix2, mix3)#

Compute thermochemical composition for the Infinite-Area-Chamber (IAC) model

This method is based on Gordon, S., & McBride, B. J. (1994). NASA reference publication, 1311.

Parameters:
  • self (struct) – Data of the mixture, conditions, and databases

  • mix2 (struct) – Properties of the mixture at the outlet of the chamber

  • mix3 (struct) – Properties of the mixture at the throat (previous calculation)

Returns:

mix3 (struct) – Properties of the mixture at the throat

guess_pressure_IAC_model(mix)#

Compute pressure guess [bar] at the throat considering an Infinite-Area-Chamber (IAC)

This method is based on Gordon, S., & McBride, B. J. (1994). NASA reference publication, 1311.

Parameters:

mix (struct) – Properties of the mixture

Returns:

pressure (float) – Pressure at the throat [bar]

guess_pressure_exit_IAC(mix2, mix3, Aratio, FLAG_SUBSONIC)#

Compute guess logarithm of the ratio pressure_inf / pressure_exit [-] for the given Area ratio [-] and indicanting if the point of interest is in the subsonic area ratios or the supersonic area ratios

Parameters:
  • mix2 (struct) – Properties of the mixture at the outlet of the chamber

  • mix3 (struct) – Properties of the mixture at the throat

  • Aratio (struct) – Ratio area_exit / area_throat

  • FLAG_SUBSONIC (bool) – Flag indicating if the Aratio refer to the subsonic region or the supersonic region

Returns:

log_P (float) – Log pressure ratio [-]

rocket_performance(self, mix1, Aratio, varargin)#

Routine that computes the propellant rocket performance

Methods implemented:
  • Infinite-Area-Chamber (IAC)

  • Finite-Area-Chamber (FAC) - NOT YET

This method is based on Gordon, S., & McBride, B. J. (1994). NASA reference publication, 1311.

Parameters:
  • self (struct) – Data of the mixture, conditions, and databases

  • mix1 (struct) – Properties of the initial mixture

  • Aratio (struct) – Ratio area_exit / area_throat

Optional Args:
  • mix2 (struct): Properties of the mixture at the outlet of the chamber (previous calculation)

  • mix3 (struct): Properties of the mixture at the throat (previous calculation)

Returns:

Tuple containing

  • mix1 (struct): Properties of the initial mixture

  • mix2 (struct): Properties of the mixture at the outlet of the chamber

  • mix3 (struct): Properties of the mixture at the throat

  • mix4 (struct): Properties of the mixture at the given exit points

solve_model_rocket(self, mix1, mix2_inj, mix2_c, mix3, mix4, Aratio)#

Compute chemical equilibria at different points of the rocket depending of the model selected

Methods implemented:
  • Infinite-Area-Chamber (IAC)

  • Finite-Area-Chamber (FAC)

This method is based on Gordon, S., & McBride, B. J. (1994). NASA reference publication, 1311.

Parameters:
  • self (struct) – Data of the mixture, conditions, and databases

  • mix1 (struct) – Properties of the initial mixture

  • mix2_inj (struct) – Properties of the mixture at the injector [only FAC] (previous calculation)

  • mix2_c (struct) – Properties of the mixture at the outlet of the chamber (previous calculation)

  • mix3 (struct) – Properties of the mixture at the throat (previous calculation)

  • mix4 (struct) – Properties of the mixture at the given exit points (previous calculation)

  • Aratio (float) – Area ratios [-]

Returns:

Tuple containing

  • mix2_1 (struct): Properties of the mixture at injector of the chamber (only FAC)

  • mix2 (struct): Properties of the mixture at the outlet of the chamber

  • mix3 (struct): Properties of the mixture at the throat

  • mix4 (struct): Properties of the mixture at the given exit points