RCAIDE.Library.Methods.Aerodynamics.Common.Drag.parasite_total

parasite_total

parasite_total(state, settings, geometry)

Computes the total parasite drag coefficient by summing contributions from all aircraft components.

Parameters:

• state (Data) –

  Flight conditions and aerodynamic state containing:

  • conditions.aerodynamics.coefficients.drag.parasitedict

    Dictionary of parasite drag coefficients indexed by component tag containing:

    • totalfloat

      Parasite drag coefficient for each component [unitless]

• settings (dict) –

  Aerodynamic analysis settings containing:

  • drag_reduction_factors.parasite_dragfloat

    Parasite drag reduction factor [unitless]

• geometry (Data) –

  Aircraft geometry containing:

  • reference_areafloat

    Vehicle reference area for drag coefficient normalization [m²]

  • wingslist

    List of wing objects containing:

    • tagstr

      Unique identifier for the wing

    • areas.referencefloat

      Reference area of the wing [m²]

  • fuselageslist

    List of fuselage objects containing:

    • tagstr

      Unique identifier for the fuselage

    • areas.front_projectedfloat

      Front projected area of the fuselage [m²]

  • boomslist

    List of boom objects containing:

    • tagstr

      Unique identifier for the boom

    • areas.front_projectedfloat

      Front projected area of the boom [m²]

  • networkslist

    List of propulsion networks containing propulsors

    • propulsorslist

      List of propulsor objects with nacelle attributes

      • nacelleNacelle, optional

        Nacelle object containing:

        • tagstr

          Unique identifier for the nacelle

        • diameterfloat

          Diameter of the nacelle [m]

Returns:

Results are stored in state.conditions.aerodynamics.coefficients.drag.parasite.total

Return type:

None

Notes

This function aggregates parasite drag contributions from all aircraft components (wings, fuselages, booms, nacelles, and pylons) and normalizes them to the vehicle reference area. The total is then adjusted by a drag reduction factor to account for interference effects and other corrections.

Major Assumptions

• Component drag coefficients are normalized to their respective reference areas

• Vehicle reference area is used for final normalization

• Drag reduction factor accounts for interference effects

• Nacelle front area is calculated as circular cross-section

• Component contributions are additive

Theory

The total parasite drag coefficient is calculated as the sum of all component contributions:

\(C_{D,parasite,total} = \sum_{i=1}^{n} C_{D,parasite,i} \cdot \frac{S_{ref,i}}{S_{ref,vehicle}}\)

where:

• \(C_{D,parasite,i}\) is the parasite drag coefficient of component \(i\)

• \(S_{ref,i}\) is the reference area of component \(i\)

• \(S_{ref,vehicle}\) is the vehicle reference area

For wings: \(S_{ref,wing} = S_{wing}\) (wing reference area)

For fuselages and booms: \(S_{ref,fuselage} = S_{front,projected}\) (front projected area)

For nacelles: \(S_{ref,nacelle} = \frac{\pi d_{nacelle}^2}{4}\) (circular cross-section area)

The final total parasite drag coefficient includes a reduction factor (user defined):

\(C_{D,parasite,final} = C_{D,parasite,total} \cdot (1 - f_{reduction})\)

where \(f_{reduction}\) is the parasite drag reduction factor.

See also

RCAIDE.Library.Methods.Aerodynamics.Common.Drag.parasite_drag_wing, RCAIDE.Library.Methods.Aerodynamics.Common.Drag.parasite_drag_fuselage, RCAIDE.Library.Methods.Aerodynamics.Common.Drag.parasite_drag_nacelle, RCAIDE.Library.Methods.Aerodynamics.Common.Drag.parasite_drag_pylon