fastoad.models.performances.mission.polar_modifier module

Aerodynamics polar modifier.

class fastoad.models.performances.mission.polar_modifier.AbstractPolarModifier[source]

Bases: ABC

Base class to implement a change to the polar during the mission computation

abstract modify_polar(polar: Polar, flight_point: FlightPoint) → Polar[source]
Parameters:

  • polar – an instance of Polar

  • flight_point – an intance of FlightPoint containg only floats

Returns:

the modified polar for the flight point

class fastoad.models.performances.mission.polar_modifier.RegisterPolarModifier(keyword='')[source]

Bases: RegisterElement

Decorator for registering AbstractPolarModifier classes.

>>> @RegisterPolarModifier("polar_modifier_foo")
>>> class FooPolarModifier(IFlightPart):
>>>     ...

Then the registered class can be obtained by:

>>> my_class = RegisterPolarModifier.get_class("polar_modifier_foo")
class fastoad.models.performances.mission.polar_modifier.UnchangedPolar[source]

Bases: AbstractPolarModifier

Default polar modifier returning the polar without changes

modify_polar(polar: Polar, flight_point: FlightPoint) → Polar[source]
Parameters:

  • polar – a polar instance

  • flight_point – a FlightPoint instance

Returns:

the polar instance

class fastoad.models.performances.mission.polar_modifier.GroundEffectRaymer(span: float, landing_gear_height: float, induced_drag_coefficient: float, k_winglet: float, k_cd: float, ground_altitude: float = 0.0)[source]

Bases: AbstractPolarModifier

Evaluates the drag in ground effect, using Raymer’s model:

‘Aircraft Design A conceptual approach’, D. Raymer p304

span: float

Wingspan

landing_gear_height: float

Main landing gear height

induced_drag_coefficient: float

Induced drag coefficient, multiplies CL**2 to obtain the induced drag

k_winglet: float

Winglet effect tuning coefficient

k_cd: float

Total drag tuning coefficient

ground_altitude: float = 0.0

Altitude of ground w.r.t. sea level

modify_polar(polar: Polar, flight_point: FlightPoint) → Polar[source]

Compute the ground effect based on altitude from ground and return an updated polar

Parameters:

  • polar – a Polar instance used as basis to apply ground effect

  • flight_point – a flight point containing the flight conditions

for calculation of ground effect :return: a copy of polar with ground effect