wingstructure.structure package¶

Submodules¶

wingstructure.structure.beammechanics module¶

class wingstructure.structure.beammechanics.Crosssection(geometries_orig, youngsmoduli, shearmoduli, thickness)¶

Bases: object

c4_point()¶

deformation_element(forces)¶

deformation_vec(forces)¶

dist_c4_shearcenter()¶

integrate_nsGt(shearforce)¶

integrate_sGt()¶

moment_shearflow(shearforce)¶

plot_around_profil(shearflow)¶

shearcenter()¶

shearflow_cell(shearforce)¶

shearflow_open(shearforce)¶

shearflow_shearforce(shearforce)¶

shearflow_torsion(torsionalmoment)¶

shearflow_total(shearforce, torsionalmoment)¶

shearforce_and_torsionalmoment(shearforce, torsionalmoment)¶

stress_element(forces)¶

test_continuity(shearflow)¶

transform_shearforce(shearforce)¶

twist(shearforce, torsionalmoment)¶

wingstructure.structure.beammechanics.EA(geometry, youngsmoduli, thickness)¶

wingstructure.structure.beammechanics.EI(geometry, youngsmoduli, thickness)¶

wingstructure.structure.beammechanics.ES(geometry, youngsmoduli, thickness)¶

wingstructure.structure.beammechanics.ES_circulate(geometry, youngsmoduli, thickness)¶

wingstructure.structure.beammechanics.lift(ρ, v, c_l, c)¶

wingstructure.structure.beammechanics.moment(ρ, v, c_m, c)¶

wingstructure.structure.beammechanics.polygonarea(polygon)¶

wingstructure.structure.beammechanics.transform(vec, Θ)¶

wingstructure.structure.internalreactions module¶

wingstructure.structure.internalreactions.calc_lineloadresultants(ys, q)¶: Calculate resultants of line loads acting on individual segments

wingstructure.structure.internalreactions.calc_moments(coords, discrete_loads)¶: Calculates cummulated forces and moments

wingstructure.structure.internalreactions.combine_loads(loadslist)¶

wingstructure.structure.mass module¶

This module contains the Masspoint class for center of gravity calculations

class wingstructure.structure.mass.Masspoint(mass: float, point: tuple)¶

Bases: object

Masspoints can be added to get the sum of masses and the common center of gravity

wingstructure.structure.material module¶

class wingstructure.structure.material.IsotropicMaterial(ρ, E, G)¶: Bases: wingstructure.structure.material._AbstractMaterial

wingstructure.structure.polygon module¶

Module for structural section analysis based on polygon geometry definition.

Inside this module basis formulas for calculation of area, static moments and moments of inertia based on polygon geometry are defined. Furthermore functions for calculation of the derived quanities neutral center and principal axis angle are included. For a simplified application to sections defined with section module the class StructuralAnalysis is also included.

Hint

All coordinate sequences passed directly to the low level functions (not the class) have to be defined in a clockwise manner.

class wingstructure.structure.polygon.StructuralAnalysis(structure)¶

Bases: object

Class for structural analysis of Sections or Features

Parameters:	structure (SectionBase or Feature) – structure element to be analysed

nc¶

Neutralcenter of structure, available after calling update

Type:	np.array

area¶

Overall Area of structure, available after calling update

Type:	float

bendingstiffness¶

bending stiffness of structure, available after calling update

Type:	np.array

update()¶

wingstructure.structure.polygon.calcarea(outline)¶

Calculate area within polygon

Parameters:	outline (np.array) – 2D coordinates of a polygon area
Returns:	area within outline
Return type:	float

wingstructure.structure.polygon.calcinertiamoments(outline)¶

Calculate moment of inertia for given polygon

Parameters:	outline (np.array) – 2D coordinates of a polygon area
Returns:	moments of inertia (I_xx, I_yy, I_xy)
Return type:	tuple(float)

wingstructure.structure.polygon.calcneutralcenter(outline)¶

Calculate the neutral center of polygon

Parameters:	outline (np.array) – 2D coordinates of a polygon area
Returns:	(x_n, y_n)
Return type:	tuple(float)

wingstructure.structure.polygon.calcprincipalaxis(I_xx, I_yy, I_xy)¶

Calculates angle of first principal axis

Parameters:	I_xx (float) – area moment of inertia I_yy (float) – area moment of inertia I_xy (float) – area moment of inertia
Returns:	principal axis angle
Return type:	float

wingstructure.structure.polygon.calcstaticmoments(outline)¶

Calculate the static moment of a polygon

Parameters:	outline (np.array) – 2D coordinates of a polygon area
Returns:	static moments
Return type:	tuple(float)

wingstructure.structure.polygon.transform_intertiamoments(I_xx, I_yy, I_xy, φ)¶

Transform moments of inertia from into rotated coordinate system

Parameters:	I_xx (float) – area moment of inertia I_yy (float) – area moment of inertia I_xy (float) – area moment of inertia φ (float) – angle to roatet
Returns:	moment of inertia in rotated coordinate system
Return type:	tuple of floats

wingstructure.structure.section module¶

Module for representation of wing section’s structure

This module defines classes which allow definition of a wing section as chain of multiple structure elements. Definition of a structure starts with SectionBase, which stores airfoil coordinates. Beginning with this exterior geometry structure elements can be added from out to inside. Possible Elements are Layers, covering the whole surface, Reinforcements for higher stiffness locally and Spar elements (ISpar and BoxSpar).

Example

import numpy as np
from wingstructure import structure

# Load cooardinates
coords = np.loadtxt('ah93157.dat', skiprows=1) * 1.2
sectionbase = structure.SectionBase(coords)

# Define Material
import collections
Material = collections.namedtuple('Material', ['ρ'])

carbonfabric = Material(1.225)
foam = Material(1.225)
sandwich = Material(1.225)

# create layers
outerlayer = structure.Layer(carbonfabric, 5e-4)
core = structure.Layer(foam, 1e-2)
innerlayer = structure.Layer(carbonfabric, 5e-4)

# create Spar
spar = structure.ISpar(material={'flange': carbonfabric, 'web': sandwich},
                       midpos=0.45,
                       flangewidth=0.2,
                       flangethickness=0.03,
                       webpos=0.5,
                       webthickness=0.02)

 # add to sectionbase
 sectionbase.extend([outerlayer, core, innerlayer, spar])

# Analyse Mass
massana = structure.MassAnalysis(sectionbase)
cg, mass = massana.massproperties()

wingstructure.structure.section.ArrayStruc¶: alias of wingstructure.structure.section.ArrayGeom

class wingstructure.structure.section.BoxSpar(material, midpos: float, width: float, flangeheigt, webwidth)¶

Bases: wingstructure.structure.section._AbstractBaseStructure

Representation for box spar

Parameters:	parent – Parent structure element. material – Material defintion. midpos (float) – Chord position of spar (absolute) width (float) – width of spar flangeheight (float) – thickness of flanges (symmetric) webwidth (float) – thickness of web

interior¶: shapely geometry representation of interior

flangeheight¶

massproperties¶

midpos¶

webwidth¶

width¶

class wingstructure.structure.section.ISpar(material, midpos: float, flangewidth: float, flangethickness: float, webpos: float, webthickness: float)¶

Bases: wingstructure.structure.section._AbstractBaseStructure

Representation for I or double-T Spar

Parameters:	parent – Parent structure element. material – Material defintion. midpos (float) – Chord position of spar (absolute) flangewidth (float) – width of flanges flangethickness (float) – thickness of flanges (symmetric) webpos (float) – position of web at flange (relative, 0 - left, 1 - right) webthickness (float) – thickness of wepropertyb

interior¶: shapely geometry representation of interior

Raises:	`Exception` – when geometry cannot be created with choosen parameters

flangethickness¶

flangewidth¶

massproperties¶

midpos¶

webpos¶

webpos_abs()¶

webthickness¶

class wingstructure.structure.section.Layer(material, thickness=0.0)¶

Bases: wingstructure.structure.section._AbstractBaseStructure

Layer of constant thickness representation

Parameters:	parent – Structure Element material – Material definition thickness (float) – The Layers geometric thickness

interior¶: shapely geometry representation of interior

enclosed_area()¶

Calculate area enclosed by centerline

Returns:	ecnlosed area
Return type:	float

middle_circumference()¶

Calculate circumference of centerline

Returns:	circumference value
Return type:	float

thickness¶

class wingstructure.structure.section.LineIdealisation(sectionbase)¶

Bases: object

Idealisation of section for structural analysis

Currently only section consisting of a I-Spar and one Layer can be idealized.

Parameters:	parent – last element of structure feature chain to be analysed

export()¶

geometry¶

class wingstructure.structure.section.MassAnalysis(sectionbase)¶

Bases: object

Analyse Mass of Structure

Parameters:	parent – last element of structure elment chain to be analysed

massproperties¶

class wingstructure.structure.section.Reinforcement(material, thickness=0.0, limits=None)¶

Bases: wingstructure.structure.section.Layer

Local reinforcement structure

Parameters:	parent – Parent structure Element material – Material Defintion thickness – reinforcement thickness limits – bounds for reinforcement in chordwise direction

interior¶: shapely geometry representation of interior

class wingstructure.structure.section.SectionBase(airfoil_coordinates)¶

Bases: object

Foundation for section’s wing structure description

Parameters:	airfoil_coordinates (np.ndarray) – airfoils coordinates from dat file

interior¶

representation of airfoil as shapely geometry

Type:	shapely.geometry.LinearRing

append(newfeature)¶

exportgeometry(refpoint=array([0., 0.]))¶

extend(newfeatures)¶

insert(index, newfeature)¶

pop()¶

remove(feature)¶

wingstructure.structure.section.geom2array(geometry, refpoint=array([0., 0.]))¶

Helper function to export polygon geometry from shapely to numpy arrays based format

Parameters:	geometry (shapely.Polygon) – Geometrie to be exported (must be a Polygon) refpoint (np.array, optional) – reference point (2D), will be substracted from coordinates (the default is np.zeros(2)
Raises:	`ValueError` – Wrong geometry type given..
Returns:	Custom geometry and material container
Return type:	ArrayStruc

wingstructure.structure.section.rework_svg(svg: str, width: float, height: float = 100.0, stroke_width: float = None) → str¶

Prettify svgs generated by shapely

Parameters:	svg (str) – svg definitiom width (float) – with of returned svg height (int, optional) – height of returned svg (the default is 100) stroke_width (float, optional) – width of lines in svg (the default is None, which [default_description])
Raises:	`Exception` – raised when input svg string is invalid
Returns:	prettified svg string
Return type:	str

wingstructure.structure package¶

Submodules¶

wingstructure.structure.beammechanics module¶

wingstructure.structure.internalreactions module¶

wingstructure.structure.mass module¶

wingstructure.structure.material module¶

wingstructure.structure.polygon module¶

wingstructure.structure.section module¶

Module contents¶

Table of Contents

Previous topic

This Page