calculate_responses3¶

Source: userfiles/SSBJ/subsystem3/calculate_responses3.py

Response calculation module for SSBJ Subsystem 3 (Structures).

This module provides structural analysis calculations for the Supersonic Business Jet (SSBJ) problem.

Functions¶

Wing_Mod(taper_ratio: float, thickness_to_chord_ratio: float, wing_sweep_angle: float, wing_aspect_ratio: float, wing_surface_area: float, tail_aspect_ratio: float, tail_surface_area: float)

Calculate wing geometry parameters.

Args:

taper_ratio: Wing taper ratio [-].
thickness_to_chord_ratio: Wing thickness-to-chord ratio [-].
wing_sweep_angle: Wing sweep angle [deg].
wing_aspect_ratio: Wing aspect ratio [-].
wing_surface_area: Wing reference surface area [ft^2].
tail_aspect_ratio: Horizontal tail aspect ratio [-].
tail_surface_area: Horizontal tail reference surface area [ft^2].

Returns:

Tuple of (c, c_box, Sweep_40, D_mx, b, l): c section chords [ft],
c_box structural box chord [ft], Sweep_40 sweep at 40% chord [deg],
D_mx load-line-to-shear-center offset [ft], b wing span [ft],
l torsion moment arm [ft].

loads(b, c, Sweep_40, D_mx, L, Izz, E)

Calculate load distribution and structural response.

Args:

b: Wing span [ft].
c: Section chord lengths [ft].
Sweep_40: Sweep angle at 40% chord [deg].
D_mx: Load-line-to-shear-center offset [ft].
L: Total lift force [lb].
Izz: Section second moment of area distribution [ft^4].
E: Young's modulus [lb/ft^2].

Returns:

Tuple of (P, Mz, Mx, bend_twist, Spanel): P shear force [lb],
Mz bending moment [lb-ft], Mx torsion moment [lb-ft],
bend_twist bending twist [deg], Spanel panel area [ft^2].

calculate_structural_responses(taper_ratio: float, alpha1: List[float], alpha3: List[float], ts2: List[float], rho1: List[float], rho2: List[float], rho3: List[float], thickness_to_chord_ratio: float, wing_sweep_angle: float, wing_aspect_ratio: float, wing_surface_area: float, tail_aspect_ratio: float, tail_surface_area: float, lift: float, h: float)

Calculate structural weights, twist, and constraint intermediate values in one pass.

The skin/sandwich thicknesses arrive in the depth-relative parametrization (see SubSystem3_Reformulation.md) and are reconstructed internally:

ts1 = 2*alpha1*D and ts3 = 2*alpha3*D (top/bottom sandwich), where the available structural depth D = beta*(t/c)*chord is rebuilt locally, so the spar-height margin becomes the linear, division-free relation h_spar = D*(1 - alpha1 - alpha3);
ts2 is the web sandwich thickness, kept absolute (inches), because the web does not set h_spar;
t_p = rho_p*ts_p (skin as a fraction of its own sandwich), so the core thickness ts_p - t_p = ts_p*(1 - rho_p) is non-negative whenever rho_p <= 1.

Args:

taper_ratio: Wing taper ratio [-].
alpha1: Length-3 top-sandwich depth fractions [-] (per spanwise station); ts1 = 2*alpha1*D.
alpha3: Length-3 bottom-sandwich depth fractions [-]; ts3 = 2*alpha3*D.
ts2: Length-3 web sandwich thicknesses [in] (absolute).
rho1: Length-3 top skin ratios [-]; t1 = rho1*ts1.
rho2: Length-3 web skin ratios [-]; t2 = rho2*ts2.
rho3: Length-3 bottom skin ratios [-]; t3 = rho3*ts3.
thickness_to_chord_ratio: Wing thickness-to-chord ratio [-].
wing_sweep_angle: Wing sweep angle [deg].
wing_aspect_ratio: Wing aspect ratio [-].
wing_surface_area: Wing reference surface area [ft^2].
tail_aspect_ratio: Horizontal tail aspect ratio [-].
tail_surface_area: Horizontal tail reference surface area [ft^2].
lift: Total lift force [lb].
h: Altitude [ft] (unused; see note below).

Returns:

Tuple of (C_structure_flat, t_ft, ts_ft, hspar_margin, Ws, Wf, theta), where t_ft and
ts_ft are the reconstructed skin/sandwich thicknesses in feet [ft] (9 values each, ordered
panel 1/2/3), hspar_margin = alpha1 + alpha3 - 0.5 [-] (3 values, one per station) is the
linear h_spar-margin constraint quantity, Ws is the structural weight [lb], Wf the
fuel weight [lb], and theta the twist-induced lift increment delta(L)/q [ft^2] (an
effective area, NOT an angle).