Composipy Classes#

This page contains Composipy classes, used to build the main instances of the package.

OrthotropicMaterial#

class composipy.OrthotropicMaterial(e1, e2, v12, g12, thickness, t1=0, c1=0, t2=0, c2=0, s=0, name=None)[source]#

Creates an OrthotropicMaterial object.

Parameters

  • e1 (float, int) – Young modulus in the 1st direction

  • e2 (float, int) – Young modulus in the 2nd direction

  • v12 (float) – poisson modulus 12

  • g12 (float, int) – Shear modulus

  • thickness (float, int) – thickness of the ply

  • t1 (float, optional, default None) – tension allowable in direction 1.

  • c1 (float, optional, default None) – compression allowable in direction 1.

  • t2 (float, optional, default None) – tension allowable in direction 2.

  • c2 (float, optional, default None) – compression allowable in direction 2.

  • s (float, optional, default None) – shear allowable.

  • name (str, optional, default None) – Name of the ply

Examples

>>> from composipy import OrthotropicMaterial
>>> ply_1 = OrthotropicMaterial(129500, 9370, 0.38, 5240, 0.2)
>>> ply_1.Q_0 # get the compliance matrix of the lamina
Out:
array([[130867.31382151,   3598.19426713,      0.     ],
    [  3598.19426713,   9468.93228191,      0.        ],
    [     0.        ,      0.        ,   5240.        ]])
Invariants()[source]#

Get the material invariants

Returns

Invariants – array([U1, U2, U3, U4, U5])

Return type

numpy.ndarray

property Q_0#

Get the compliance matrix of the material.

Returns

self.Q_0 – Compliance matrix (3x3) of the Material

Return type

numpy.ndarray

LaminateProperty#

class composipy.LaminateProperty(stacking, plies)[source]#

This class creates a LaminateProperty object. It requires Material objects (to define plies) and angle information. Some formulation characteristics are: - Laminate formulations are used (see References). - The main reference is Chapter 4 of Reference 2.

Parameters

  • stacking (list or dict) –

    To define a angle stacking sequence

    An iterable containing the angles (in degrees) of layup.

    To define a stack based on lamination parameters.

    {xiA: [xiA1, xiA2, xiA3, xiA4], xiB: [xiB1, xiB2, xiB3, xiB4], xiD: [xiD1, xiD2, xiD3, xiD4], T: thickness}

  • plies (Material or list) – A single Material or a list of OrthotropicMaterial object

Example

>>> from composipy import OrthotropicMaterial, LaminateProperty
>>> ply_1 = OrthotropicMaterial(129500, 9370, 0.38, 5240, 0.2)
>>> stacking = [90, 0, 90]
>>> laminate_1 = Laminate(stacking, ply_1)
>>> laminate_1.ABD # retunrs an array containing bending stiffness matrix [D] of the laminate
>>> laminate_1.xiA # lamination parameters of extension
>>> laminate_1.xiA # lamination parameters of bending

Example

>>> stacking = {'xiD': [0., 0., -1., 0.], 'T': 1.0} #using lamination parameters to define D
>>> laminate_2 = Laminate(stacking, ply_1)
>>> laminate_2.ABD # retunrs an array containing bending stiffness matrix [D] of the laminate
>>> laminate_2.xiA # lamination parameters of extension
>>> laminate_2.xiA # lamination parameters of bending

Note

The first element of the stacking list corresponds to the BOTTOM OF THE LAYUP, and the last element corresponds to the TOP OF THE LAYUP. This is important for non-symmetric laminates.

Refer to rafaelpsilva07/composipy#28.

property A#

[A] Matrix as numpy.ndarray

property ABD#

[ABD] Matrices as numpy.ndarray

property B#

[B] Matrix as numpy.ndarray

Note

Matrix [B] will be zero if defined using lamination parameters.

property D#

[D] Matrix as numpy.ndarray

property xiA#

Lamination parameter xiA

property xiD#

Lamination parameter xiD

PlateStructure#

class composipy.PlateStructure(dproperty, a, b, constraints={'x0': ['TX', 'TY', 'TZ'], 'xa': ['TX', 'TY', 'TZ'], 'y0': ['TX', 'TY', 'TZ'], 'yb': ['TX', 'TY', 'TZ']}, Nxx=0, Nyy=0, Nxy=0, m=10, n=10)[source]#

This class defines a PlateStructure.

Parameters

  • dproperty (composipy.Property) – Property of the plate.

  • a (float) – Size of the plate parallel to the x axis.

  • b (float) – Size of the plate parallel to the y axis.

  • constraints (str or dict. Default: "PINNED") – Plate boundary conditions.

  • Nxx (float, default 0) – Linear force parallel x axis

  • Nyy (float, default 0) – Linear force parallel y axis

  • Nxy (float, default 0) – Linear shear force

  • m (int, default 10) – Size of shape function along x axis

  • n (int, default 10) – Size of shape function along y axis

Example

>>> from composipy import OrthotropicMaterial, LaminateProperty, PlateStructure
>>> ply_1 = OrthotropicMaterial(129500, 9370, 0.38, 5240, 0.2)
>>> stacking = [90, 0, 90]
>>> laminate = Laminate(stacking, ply_1)
>>> constraints

Note

The constraint argument can be a str type ‘PINNED’ or ‘CLAMPED’. Or a dictionary like described below:

>>> constraints = {
---     x0 = ['TX', 'TY', 'TZ', 'RX', 'RY', 'RZ']
---     xa = ['TX', 'TY', 'TZ', 'RX', 'RY', 'RZ']
---     y0 = ['TX', 'TY', 'TZ', 'RX', 'RY', 'RZ']
---     yb = ['TX', 'TY', 'TZ', 'RX', 'RY', 'RZ']
--- }

Attention, the rotations aren’t considered around the axis. They are related to the shape function. That means, for example, the RZ turns around the x axis and moves the plate in z direction.

buckling_analysis(silent=True, num_eigvalues=5)[source]#

Linear Buckling Analysis

Parameters

  • silent (bool, optional) – Prints time to compute calculation

  • num_eigvalues (int, optional) – Number of calculated eigenvalues.

Return type

eigvals, eigvecs

calc_K_KG_ABD()[source]#

Calculates the stiffness and geometrical stifness matrices. Considers full ABD matrix.

Returns

K_KG – A tuple of array containing (K, KG)

Return type

tuple

calc_K_KG_D()[source]#

Calculates the stiffness and geometrical stifness matrices. Considers only the bending stiffness D matrix.

Returns

K_KG – A tuple of array containing (K, KG)

Return type

tuple

LaminateStrength#

class composipy.LaminateStrength(dproperty, Nxx=0, Nyy=0, Nxy=0, Mxx=0, Myy=0, Mxy=0)[source]#

Creates a LaminateStrength object to evaluate strength. The class is capable of calculating strain and stress at the midplane, as well as ply-by-ply at the top and bottom, both in the laminate and material directions.

Parameters

  • dproperty (LaminateProperty) – A laminate property object

  • Nxx (float, int, optional, default 0) – Membrane load in x direction.

  • Nyy (float, int, optional, default 0) – Membrane load in y direction.

  • Nxy (float, int, optional, default 0) – Membrane load in xy direction.

  • Mxx (float, int, optional, default 0) – Moment in x direction.

  • Myy (float, int, optional, default 0) – Moment in y direction.

  • Mxy (float, int, optional, default 0) – Moment in xy direction.

calculate_strain()[source]#

Calculates strain ply by at laminate direction and material direction.

Returns

strains – ply by ply strains in plate direction and material direction

Return type

pd.Dataframe

Note

The sequence of the DataFrame starts from the TOP OF THE LAYUP to the BOTTOM OF THE LAYUP, which is the reverse of the definition order. When defining the laminate, the first element of the list corresponds to the bottom-most layer. This is especially important for non-symmetric laminates.

calculate_stress()[source]#

Calculates stress ply by at laminate direction and material direction.

Returns

stress – ply by ply stress in plate direction and material direction

Return type

pd.Dataframe

Note

The sequence of the DataFrame starts from the TOP OF THE LAYUP to the BOTTOM OF THE LAYUP, which is the reverse of the definition order. When defining the laminate, the first element of the list corresponds to the bottom-most layer. This is especially important for non-symmetric laminates.

epsilon0()[source]#

Calculates the strains of the laminate

Returns

epsilon0 – [epsilonx0, epsilony0, epsilonxy0, kappax0, kappay0, kappaxy0]

Return type

numpy ndarray

On this page
Show Source