flight_mech.atmosphere module#

Module providing simple atmospheric models.

class flight_mech.atmosphere.AtmosphereModel[source]#

Bases: ABC

Atmosphere abstract class.

abstract static compute_altitude_from_sigma(sigma: float) → float[source]#

Compute the altitude corresponding to the given density coefficient.

Parameters:

sigma (float) – Density coefficient.

Returns:

Altitude in meters.

Return type:

float

abstract classmethod compute_density_from_altitude(z: float) → float[source]#

Compute the air density.

Parameters:

z (float) – Altitude in meters.

Returns:

Air density in kg.m-3

Return type:

float

abstract static compute_sigma_from_altitude(z: float) → float[source]#

Compute the density coefficient sigma.

Parameters:

z (float) – Altitude in meters.

Returns:

Density coefficient.

Return type:

float

gas_model: GasModel#
plot_graph(variable: Literal['pressure', 'temperature', 'density', 'sound_speed', 'dynamic_viscosity'], min_altitude: float = 0.0, max_altitude: float = 20000.0, nb_points: int = 100, **kwargs)[source]#

Plot the graph of evolution of the given variable in the atmosphere.

Parameters:

  • variable (Literal["pressure", "temperature", "density", "sound_speed", "dynamic_viscosity"]) – Name of the variable to plot.

  • min_altitude (float, optional) – Minimum altitude on the plot in meters, by default 0.

  • max_altitude (float, optional) – Maximum altitude on the plot in meters, by default 20000.

  • nb_points (int, optional) – Number of points in the plot.

Note

For more details on the optional arguments, please check flight_mech._common.plot_graph.

class flight_mech.atmosphere.ConstantAtmosphere[source]#

Bases: AtmosphereModel

A constant atmosphere model. Used for test purposes only.

static compute_altitude_from_sigma(sigma: float)[source]#

Compute the altitude corresponding to the given density coefficient.

Parameters:

sigma (float) – Density coefficient.

Returns:

Altitude in meters.

Return type:

float

classmethod compute_density_from_altitude(z: float)[source]#

Compute the air density.

Parameters:

z (float) – Altitude in meters.

Returns:

Air density in kg.m-3

Return type:

float

static compute_sigma_from_altitude(z: float)[source]#

Compute the density coefficient sigma.

Parameters:

z (float) – Altitude in meters.

Returns:

Density coefficient.

Return type:

float

gas_model: GasModel = <flight_mech.gas.Air object>#
class flight_mech.atmosphere.LinearAtmosphere[source]#

Bases: AtmosphereModel

A very basic linear model for the atmosphere allowing to compute the density only.

static compute_altitude_from_sigma(sigma: float)[source]#

Compute the altitude corresponding to the given density coefficient.

Parameters:

sigma (float) – Density coefficient.

Returns:

Altitude in meters.

Return type:

float

classmethod compute_density_from_altitude(z: float)[source]#

Compute the air density.

Parameters:

z (float) – Altitude in meters.

Returns:

Air density in kg.m-3

Return type:

float

static compute_sigma_from_altitude(z: float)[source]#

Compute the density coefficient sigma.

Parameters:

z (float) – Altitude in meters.

Returns:

Density coefficient.

Return type:

float

gas_model: GasModel = <flight_mech.gas.Air object>#
class flight_mech.atmosphere.StandardAtmosphere[source]#

Bases: AtmosphereModel

International Standard Atmosphere model to compute pressure, temperature and density with altitude.

Notes

For more details, see: https://en.wikipedia.org/wiki/International_Standard_Atmosphere. For the original paper, see: https://www.digitaldutch.com/atmoscalc/US_Standard_Atmosphere_1976.pdf.

classmethod compute_altitude_from_sigma(sigma: float)[source]#

Compute the altitude from a given density ratio. This only works for altitude below 20km.

Parameters:

z (float) – Density ratio.

Returns:

Altitude in m.

Return type:

float

classmethod compute_density_from_altitude(z: float)[source]#

Compute the air density.

Parameters:

z (float) – Altitude in meters.

Returns:

Air density in kg.m-3

Return type:

float

classmethod compute_dynamic_viscosity_from_altitude(z: float)[source]#

Compute the dynamic viscosity at a given altitude.

Parameters:

z (float) – Altitude in meters.

Returns:

Dynamic viscosity in kg.m-1.s-1.

Return type:

float

classmethod compute_kinematic_viscosity_from_altitude(z: float)[source]#

Compute the kinematic viscosity at a given altitude.

Parameters:

z (float) – Altitude in meters.

Returns:

Kinematic viscosity in m2.s-1.

Return type:

float

static compute_pressure_from_altitude(z: float)[source]#

Compute the pressure at a given altitude.

Parameters:

z (float) – Altitude in meters.

Returns:

Air pressure in Pa.

Return type:

float

classmethod compute_sigma_from_altitude(z: float)[source]#

Compute the density coefficient sigma.

Parameters:

z (float) – Altitude in meters.

Returns:

Density coefficient.

Return type:

float

classmethod compute_sound_speed_from_altitude(z: float)[source]#

Compute the sound speed at a given altitude.

Parameters:

z (float) – Altitude in meters.

Returns:

Sound speed in m.s-1.

Return type:

float

static compute_temperature_from_altitude(z: float)[source]#

Compute the temperature at a given altitude.

Parameters:

z (float) – Altitude in meters.

Returns:

Air temperature in K.

Return type:

float

gas_model: GasModel = <flight_mech.gas.Air object>#
classmethod update_gas_model_to_altitude_conditions(z: float)[source]#