pyva.systems.infiniteLayers.PerforatedLayer

class pyva.systems.infiniteLayers.PerforatedLayer(thickness, hole_radius, fluid=Fluid(c0=343.0, rho0=1.23, eta=0.01), pattern='square', alpha=2.0, **kwargs)

Bases: ResistiveLayer

The PerforatedLayer class deals perforated layers in acoustic networks

The behaviour is calculated using flow throught the holes and radiation be the disk radiator pattern

thickness

thickness of the perforted layer

Type:: float

pattern

identifier for hole pattern (quadradic, triangular, )

Type:: str

hole_radius

radius of the holes in the membrane

Type:: float

porosity

area ratio of holes to totalsurface

Type:: float

fluid

fluid in the hole

Type:: fluid

alpha

correction constant for resistivity correction approx 4.-2. for sharp to round edges

Type:: float

area mass

area mass, when > 0 the perforate is considered as limp

Type:: float

__init__(thickness, hole_radius, fluid=Fluid(c0=343.0, rho0=1.23, eta=0.01), pattern='square', alpha=2.0, **kwargs)

Class contructor for PerforatedLayer

Parameters:

thickness (float) – thickness of the perforted layer
hole_radius (float) – radius of the holes in the membrane
fluid (fluid) – fluid in the hole. The default is visc_air.
pattern (str) – identifier for hole pattern (‘square’,triangular’’,). The default is ‘square’.
alpha (float) – correction constant for resistivity correction approx 4.-2. for sharp to round edges: The default is 2.
**kwargs (dict) – arbitrary keyword parameter list
distance (float) – distance between holes
porosity (float) – surface porosity of perforate

Return type:

None.

Methods

`__init__`(thickness, hole_radius[, fluid, ...])	Class contructor for PerforatedLayer
`get_xdata`(omega, kx)	Determine the appropriate xdata from omega and kx.
`plot`(omega, **kwargs)	Plots the transfer impedance for the related part
`transfer_impedance`(omega[, kx, ID])	Transferimpedance of perforateLayer

Attributes

`isequivalentfluid`	Determine if layer is of type equivalent fluid
`porosity`	porosity parameter
`visc_air`

static get_xdata(omega, kx)

Determine the appropriate xdata from omega and kx.

Infinite Layer theory often involves integration over wavenumber. Thus, the kx is the integration variable.

If omega is scalar xdata will be wavenumber in x (kx) if kx is scalar xdata will be angular frequency if kx and omega have same dimension it is assumed that kx belongs to a constant angle and is given by kx = omega/c0*sin(theta) and xdata will be angular frequency

Parameters:

omega (float or ndarray) – angular frequency
kx (float or ndarray) – wavenumber

Returns:

wavenumber or omega as DataAxis object

Return type:

DataAxis

property isequivalentfluid

Determine if layer is of type equivalent fluid

Defauls parameter is True

Returns:: True.
Return type:: bool

plot(omega, **kwargs)

Plots the transfer impedance for the related part

Parameters:

omega (float) – angular frequency.
fig (int, optional) – figure ID. The default is 1.
**kwargs (dict) – Arbitrary keyword parameter list passed to Signal.plot.

Return type:

None.

property porosity

porosity parameter

Return type:: None.

transfer_impedance(omega, kx=0, ID=[1, 2])

Transferimpedance of perforateLayer

The transferimpedance is caluclated based on the lumped_acoustic model, because it is independent from the kx

Parameters:

omega (float or ndarray) – scalar angular frequency
kx (float or ndarray, optional) – In-plane wavenumber. The default is 0.
ID (list of int, optional) – Left and right when overwritten, None takes object ID. The default is None.

Returns:

[2 x 2] array of transferimpedance

Return type:

DynamicMatrix