Blade-Stiffened Cylinder#

compmech.panel.assembly.cylinder_blade_stiffened.create_cylinder_blade_stiffened(height, r, stack, stack_blades, width_blades, plyt, laminaprop, npanels, m=8, n=8)[source]#

Cylinder Assembly

The panel assembly looks like:

B                               A
 _______ _______ _______ _______
|       |       |       |       |
|       |       |       |       |
|       |       |       |       |
|  p04  |  p03  |  p02  |  p01  |
|       |       |       |       |
|       |       |       |       |
|_______|_______|_______|_______|

Blade   Blade   Blade   Blade
04      03      02      01
 _       _       _       _
| |     | |     | |     | |
| |     | |     | |     | |
| |     | |     | |     | |
| |     | |     | |     | |
|_|     |_|     |_|     |_|
                                       x
                                     /\
                                     |
                                     |
                           y  <-------

where edges A and B are connected to produce the cyclic effect.

Parameters:

heightfloat: Cylinder height (along \(x\)).
rfloat: Cylinder radius.
stackarray-like: Stacking sequence for the cylinder.
stack_bladeslist of array-like: The stacking sequence for each blade (with length = npanels).
width_bladesarray-like: The width for each blade (with length = npanels).
plytfloat: Ply thickness (assumed unique for the whole structure).
laminaproplist or tuple: Orthotropic lamina properties: \(E_1, E_2, \nu_{12}, G_{12}, G_{13}, G_{23}\).
npanelsint: The number of panels the cylinder perimiter.
m, nint, optional: Number of approximation terms for each panel.

Returns:

assy, connstuple: A tuple containing the assembly and the default connectivity list of dictionaries.

compmech.panel.assembly.cylinder_blade_stiffened.cylinder_blade_stiffened_compression_lb_Nxx_cte(height, r, stack, stack_blades, width_blades, plyt, laminaprop, npanels, Nxxs_skin, Nxxs_blade, m=8, n=8, num_eigvalues=20)[source]#

Linear buckling analysis with a constant Nxx for each panel

See create_cylinder_blade_stiffened() for most parameters.

Parameters:

Nxxs_skinlist: A Nxx for each skin panel.
Nxxs_bladelist: A Nxx for each blade stiffener.
num_eigvaluesint: Number of eigenvalues to be extracted.

Returns:

assy, eigvals, eigvecstuple: Assembly, eigenvalues and eigenvectors.

Examples

The following example is one of the test cases:

def test_cylinder_blade_stiffened_compression_lb_Nxx_cte():
    print('Testing assembly function: cylinder_blade_stiffened_compression_lb_Nxx_cte')
    height = 0.500
    r = 0.250
    npanels = 5
    Nxxs = [-100.]*npanels
    assy, eigvals, eigvecs = cylinder_blade_stiffened_compression_lb_Nxx_cte(
        height=height,
        r=r,
        plyt=0.125e-3,
        stack=[0, 45, -45, 90, -45, 45],
        stack_blades=[[0, 90, 0]*4]*npanels,
        width_blades=[0.02]*npanels,
        laminaprop=(142.5e9, 8.7e9, 0.28, 5.1e9, 5.1e9, 5.1e9),
        npanels=npanels,
        Nxxs_skin=Nxxs,
        Nxxs_blade=Nxxs,
        m=8, n=12)

    assy.plot(eigvecs[:, 0], 'skin', filename='tmp_cylinder_blade_stiffened_compression_lb_Nxx_cte.png')

    assert np.isclose(Nxxs[0]*eigvals[0], -56569.62172, atol=0.01, rtol=0.001)

compmech.panel.assembly.cylinder_blade_stiffened.cylinder_blade_stiffened_compression_lb_Nxx_from_static(height, r, stack, stack_blades, width_blades, plyt, laminaprop, npanels, Nxxs_skin, Nxxs_blade, m=8, n=8, num_eigvalues=20)[source]#

Linear buckling analysis with a Nxx calculated using static analysis

See create_cylinder_blade_stiffened() for most parameters.

Parameters:

Nxxs_skinlist: A Nxx for each skin panel.
Nxxs_bladelist: A Nxx for each blade stiffener.
num_eigvaluesint: Number of eigenvalues to be extracted.

Returns:

assy, c, eigvals, eigvecstuple: Assembly, static results, eigenvalues and eigenvectors.

Examples

The following example is one of the test cases: