CL_max_critical_section.py

@File : CLmax_jet_transport.py @Date : 2023/04/11 @Author : Eytan Adler @Description : Max lift coefficient estimate using critical section method

class openconcept.aerodynamics.openaerostruct.CL_max_critical_section.CLmaxCriticalSectionVLM(**kwargs)

Bases: Group

Predict the maximum lift coefficient of the wing by solving for the angle of attack where the maximum sectional lift coefficient equals the provided maximum lift coefficient of the airfoil. The solution for the sectional lift coefficients is done using OpenAeroStruct.

Inputs:

  • ac|aero|airfoil_Cl_max (float) – Maximum 2D lift coefficient of the wing airfoil (scalar or, if vec_Cl_max is set to true, vector of length num_y, dimensionless)

  • fltcond|M (float) – Mach number for maximum CL calculation (scalar, dimensionless)

  • fltcond|h (float) – Altitude for maximum CL calculation (scalar, m)

  • fltcond|TempIncrement (float) – Temperature increment for maximum CL calculation (scalar, degC)

  • ac|geom|wing|OAS_mesh (float) – OpenAeroStruct 3D mesh (num_x + 1 x num_y + 1 x 3 vector, m)

  • ac|geom|wing|toverc (float) – Thickness to chord ratio of each streamwise strip of panels ordered from wing tip to wing root; used for the viscous and wave drag calculations (vector of length num_y, dimensionless)

Outputs:

CL_max (float) – Maximum lift coefficient estimated using the critical section method (scalar, dimensionless)

Options:

  • num_x (int) – Number of panels in x (streamwise) direction (scalar, dimensionless)

  • num_y (int) – Number of panels in y (spanwise) direction for one wing because uses symmetry (scalar, dimensionless)

  • vec_Cl_max (bool) – Make the input ac|aero|airfoil_Cl_max a vector of length num_y where each item in the vector is a spanwise panel’s local maximum lift coefficient, ordered from wing tip to root. This enables specification of a varying maximum sectional lift coefficient along the span, which can be used to model high lift devices on only a portion of the wing. If this option is False, ac|aero|airfoil_Cl_max is a scalar, which represents the maximum airfoil lift coefficient across the entire span of the wing, by default False

  • surf_options (dict) – Dictionary of OpenAeroStruct surface options; any options provided here will override the default ones; see the OpenAeroStruct documentation for more information. Because the geometry transformations are excluded in this model (to simplify the interface), the <transformation>_cp options are not supported. The t_over_c option is also removed since it is provided instead as an input.

  • rho (float or int) – Constraint aggregation factor for sectional lift coefficient aggregation, by default 200