pyva.coupling.junctions.AreaJunction

class pyva.coupling.junctions.AreaJunction(systems, area=0)

Bases: Junction

Class for Area Junctions between plates and cavities

systems

connected systems

Type:: list or tuple

area

area of AreaJunction

Type:: float

double_cavity

switch for simple cavity-cavity connection

Type:: bool

cavity1

first connected cavity

Type:: Acoustic3DSystem

cavity2

second connected cavity

Type:: Acoustic3DSystem

plate

plate subsysten

Type:: Structure2DSystem

ix_plate

index of plate subsystem in list

Type:: int

__init__(systems, area=0)

Class contructor for AreraJunction

Possible system configurations are:: cavity - plate - cavity cavity - cavity plate - cavity cavity - plate

Parameters:

systems (list) – involved systems
area (float) – area of area junction

Examples

Methods

`CLF`(omega[, i_sys, i_in_wave, i_out_wave, ...])	coupling loss factor for area junctions
`CLF_fluid_fluid`(omega[, pos_dir, theta_max])	Calculates the coupling loss factor of fluid fluid junctions
`CLF_structure_fluid`(omega[, ix_cavity, pos_dir])	Calculates the coupling loss factors of plate to fluid junctions
`__init__`(systems[, area])	Class contructor for AreraJunction
`get_wave_DOF`([ix])	Provides the local wave DOFs of the area junction
`index`(ID)	Determines index of ID in system list of junction
`junction_matrix`(omega[, N_step, method, Signal])	Calculates the local SEA matrix for the junction DOFs
`modal_density`(omega)	Provides modal density

Attributes

`N`	Number of connected physical SEA systems (not wave_fields)
`N_wave`	Number of wave fields
`exc_DOF`	Provides 'excitation' DOFs of junction SEA matrix
`in_dofs`	Provides input wave dofs of junction for upper triangular input matrix
`out_dofs`	Provides output wave dofs of junction for upper triangular input matrix
`res_DOF`	Provides 'response' DOFs of junction SEA matrix

CLF(omega, i_sys=(0, 1), i_in_wave=(0, 0), i_out_wave=(0, 0), N_step=90, method='diffuse', Signal=True)

coupling loss factor for area junctions

This method calculates the CLF from system i_sys[0] to i_sys[1] and calls the appropriate CLF_fluid_fluid or CLF_structure_fluid method

Parameters:

omega (float) – angular frequency.
i_sys (tuple, list of ndarray, optional) – 2x1 vector of input output index. The default is (0,1).
i_in_wave (int, optional) – index of in wave. The default is (0,0).
i_out_wave (int, optional) – index of out wave. The default is (0,0).
N_step (int, optional) – Integration steps for diffuse field integration. The default is 90.
method (str, optional) – method str for selection of calculation method. The default is ‘diffuse’.
Signal (bool, optional) – switch for Signal output. The default is True.

Returns:

CLF.

Return type:

Signal or ndarray

CLF_fluid_fluid(omega, pos_dir=True, theta_max=1.361356816555577)

Calculates the coupling loss factor of fluid fluid junctions

The infinite layer method is used here for the mass law and non-resonant coupling

Parameters:

omega (TYPE) – angular frequency.
pos_dir (bool, optional) – switch for direction of wave transfer. The default is True.
theta_max (float, optional) – Maximum angle for diffuse field integration. The default is np.pi/180*78.

Returns:

eta_non_res – CLF.

Return type:

ndarray

CLF_structure_fluid(omega, ix_cavity=0, pos_dir=True)

Calculates the coupling loss factors of plate to fluid junctions

Parameters:

omega (float) – angular frequency.
ix_cavity (int, optional) – index of cavity. The default is 0.
pos_dir (bool, optional) – swith for direction. True means from plate to cavity. The default is True.

Returns:

coupling loss factor.

Return type:

ndarray

property N

Number of connected physical SEA systems (not wave_fields)

Returns:: number of systems
Return type:: int

property N_wave

Number of wave fields

Returns:: Number of wave fields
Return type:: int

property exc_DOF

Provides ‘excitation’ DOFs of junction SEA matrix

The ‘excitation’ and response DOFs are equal in terms of ID and wave_dof but use ‘power’ as physical input

Returns:: excitation DOFs of junction SEA matrix
Return type:: DOF

get_wave_DOF(ix=slice(None, None, None))

Provides the local wave DOFs of the area junction

Parameters:: ix (int, optional) – DESCRIPTION. The default is slice(None,None).
Returns:: ldofs of junction systems participating to junction DESCRIPTION.
Return type:: DOF

property in_dofs

Provides input wave dofs of junction for upper triangular input matrix

These DOFs are requiered to determine the column index of the upper triangular components in the global SEA matrix.

For example a plate - cavity junction has wave dofs [ ID=1,dof=3 ; 1,5 ; 2,0 ]

The full of diag CLF in the SEA matrix are

$\begin{bmatrix} \Sigma & - n_{15}\eta_{15,13} & -n_{20}\eta_{20,13} \\ - n_{13}\eta_{13,15} & \Sigma & -n_{20}\eta_{20,15} \\ - n_{13}\eta_{13,20} & - n_{15}\eta_{15,20} & \Sigma \end{bmatrix}$

The column dofs would be : [ 1,5 ; 2,0 ; 2,0]