from __future__ import annotations
from osaft import log
from osaft.core.backgroundfields import BackgroundField, WaveType
from osaft.core.basecomposite import BaseSphereFrequencyComposite
from osaft.core.fluids import InviscidFluid, ViscousFluid
from osaft.core.frequency import Frequency
from osaft.core.functions import pi, sin
from osaft.core.geometries import Sphere
from osaft.core.helper import StringFormatter as SF
from osaft.core.variable import ActiveVariable
from osaft.core.warnings import EPS, raise_assumption_warning
from osaft.solutions.base_arf import BaseARF
from osaft.solutions.base_solution import BaseSolution
[docs]class ARF(BaseARF, BaseSphereFrequencyComposite, BaseSolution):
"""ARF class for Settnes and Bruus (2012)
The standing wave solution is based on Eqs. (50a) - (50b) of the
paper and the
traveling wave solution on Eq (48).
.. note::
This model is based on the following assumptions:
- :math:`\\lambda \\gg R_0, \\, \\delta`
.. note::
The expression for the travelling wave has been corrected. The
expression in the article by Settnes & Bruus was off by a factor of 2.
The error was reported in an article
`Marston (2013) <https://asa.scitation.org/doi/pdf/10.1121/1.4799400>`_
:param f: Frequency [Hz]
:param R_0: Radius of the sphere [m]
:param rho_s: Density of the sphere [kg/m^3]
:param c_s: Speed of sound of the fluid-like sphere [m/s]
:param rho_f: Density of the fluid [kg/m^3]
:param c_f: Speed of sound of the fluid [m/s]
:param eta_f: Dynamic viscosity of the fluid [Pa s]
:param p_0: Pressure amplitude of the field [Pa]
:param wave_type: Type of incident wave (traveling/standing)
:param position: Position in the standing wave field [rad]
"""
# Supported wave_type for the class
supported_wavetypes = [WaveType.STANDING, WaveType.TRAVELLING]
def __init__(
self,
f: Frequency | float | int,
R_0: Sphere | float | int,
rho_s: float,
c_s: float,
rho_f: float,
c_f: float,
eta_f: float,
p_0: float,
wave_type: WaveType,
position: None | float = None,
) -> None:
"""Constructor method"""
# init of parent class
# init of parent class
BaseSphereFrequencyComposite.__init__(self, f, R_0)
BaseSolution.__init__(self, "Settnes2012")
# Initialize Components
self.scatterer = InviscidFluid(self.frequency, rho_s, c_s)
self.fluid = ViscousFluid(self.frequency, rho_f, c_f, eta_f, 0)
self.field = BackgroundField(self.fluid, p_0, wave_type, position)
# Dependent variables
self._f_1 = ActiveVariable(
self._compute_f_1,
"monopole scattering coefficient f_1",
)
self._f_2 = ActiveVariable(
self._compute_f_2,
"dipole scattering coefficient f_2",
)
self._gamma = ActiveVariable(
self._compute_gamma,
"dimensionless variable gamma",
)
self._delta_t = ActiveVariable(
self._compute_delta_t,
"dimensionless boundary layer " "thickness",
)
self._kappa_t = ActiveVariable(
self._compute_kappa_t,
"compressibility ratio kappa tilde",
)
self._rho_t = ActiveVariable(
self._compute_rho_t,
"density ratio rho tilde",
)
self._Phi = ActiveVariable(
self._compute_Phi,
"acoustic contrast factor Phi",
)
# Dependencies
self._f_1.is_computed_by(self._kappa_t)
self._f_2.is_computed_by(self._rho_t, self._gamma)
self._delta_t.is_computed_by(self.fluid._delta, self.sphere._R_0)
self._gamma.is_computed_by(self._delta_t)
self._kappa_t.is_computed_by(
self.fluid._kappa_f,
self.scatterer._kappa_f,
)
self._rho_t.is_computed_by(self.fluid._rho_f, self.scatterer._rho_f)
self._Phi.is_computed_by(self._f_1, self._f_2)
log.info(str(self))
log.debug(repr(self))
[docs] def compute_arf(self) -> float:
"""Computes the ARF and returns the force in Newton [N].
Computes ARF according to Eq. (47a) - (47e) for standing wave case
or according to Eq. (48) for the travelling wave case.
Checks before computation of assumption of theory small particle
radius to pressure field wavelength is valid.
:raises WrongWaveTypeError: if wrong :attr:`wave_type`
:raises AssumptionWarning: if the used parameters might not be
valid for the chosen limiting case
"""
# Checking wave_type
self.check_wave_type()
# size limitation in section IV.D of paper
test_value = self.R_0 < EPS * self.field.lambda_f
test_value = test_value and self.delta < EPS * self.field.lambda_f
raise_assumption_warning(test_value)
# Cases
if self.wave_type == WaveType.STANDING:
return self._standing_wave_solution()
else:
return self._traveling_wave_solution()
def _standing_wave_solution(self) -> float:
out = 4 * pi * self.E_ac * self.R_0**3 * self.k_f.real
out *= self.Phi * sin(2 * self.position)
return out
def _traveling_wave_solution(self) -> float:
# This expression has been corrected according to Marston (2013).
return (
2 * pi * self.R_0**3 * self.k_f.real * self.f_2.imag * self.E_ac
)
def __repr__(self):
return (
f"SettnesARF({self.f}, {self.R_0}, {self.rho_s}, "
f"{self.c_s}, {self.rho_f}, {self.c_f}, {self.eta_f}"
f"{self.wave_type}, {self.p_0}, {self.position}"
)
def __str__(self):
out = "Settnes' & Bruus' solution with following properties: \n"
out += SF.get_str_text("Frequency", "f", self.f, "Hz")
out += SF.get_str_text("Pressure", "p_0", self.p_0, "Pa")
out += SF.get_str_text(
"Position",
"d",
self.position,
"rad",
)
out += SF.get_str_text(
"Wave Type",
"",
self.wave_type,
None,
)
out += SF.get_str_text(
"Wavelength",
"lambda",
self.field.lambda_f,
"m",
)
out += "Fluid\n"
out += SF.get_str_text(
"Density",
"rho_f",
self.rho_f,
"kg/m^3",
)
out += SF.get_str_text(
"Sound Speed",
"c_0",
self.c_f,
"m/s",
)
out += SF.get_str_text(
"Viscosity",
"eta_f",
self.eta_f,
"Pa s",
)
out += SF.get_str_text(
"Compressibility",
"kappa_f",
self.kappa_f,
"1/Pa",
)
out += "Particle\n"
out += SF.get_str_text(
"Radius",
"R_0",
self.R_0,
"m",
)
out += SF.get_str_text(
"Density",
"rho_s",
self.rho_s,
"kg/m^3",
)
out += SF.get_str_text(
"Speed of Sound",
"c_s",
self.scatterer.c_f,
"m/s",
)
out += SF.get_str_text(
"Compressibility",
"kappa_s",
self.kappa_s,
"1/Pa",
False,
)
return out
# -------------------------------------------------------------------------
# Getters for Dependent Variables
# -------------------------------------------------------------------------
@property
def f_1(self) -> float:
"""Monopole scattering coefficient :math:`f_1` [-]
(Eq. 26)
"""
return self._f_1.value
@property
def f_2(self) -> complex:
"""Dipole scattering coefficient :math:`f_2` [-]
(Eq. 39)
"""
return self._f_2.value
@property
def delta_t(self) -> float:
"""Normalized boundary layer thickness :math:`\\tilde{\\delta}` [-]
(Eq. 34)
"""
return self._delta_t.value
@property
def gamma(self) -> complex:
"""Dimensionless variable :math:`\\gamma` [-]
(Eq. 38)
"""
return self._gamma.value
@property
def kappa_t(self) -> float:
"""Compressibility ratio :math:`\\tilde{\\kappa}` [-]
(Eq. 26)
"""
return self._kappa_t.value
@property
def rho_t(self) -> float:
"""Density ratio :math:`\\tilde{\\rho}` [-]
(Eq. 39)
"""
return self._rho_t.value
@property
def Phi(self) -> float:
"""Acoustic contrast factor :math:`\\Phi` [-]"""
return self._Phi.value
# -------------------------------------------------------------------------
# Wrappers for Independent Field Attributes
# -------------------------------------------------------------------------
@property
def position(self) -> float:
"""Wraps to
:attr:`osaft.core.backgroundfields.BackgroundField.position`
"""
return self.field.position
@position.setter
def position(self, value: float) -> None:
self.field.position = value
@property
def p_0(self) -> float:
"""Wraps to
:attr:`osaft.core.backgroundfields.BackgroundField.p_0`
"""
return self.field.p_0
@p_0.setter
def p_0(self, value: float) -> None:
self.field.p_0 = value
@property
def wave_type(self) -> WaveType:
"""Wraps to
:attr:`osaft.core.backgroundfields.BackgroundField.wave_type`
"""
return self.field.wave_type
@wave_type.setter
def wave_type(self, value: WaveType) -> None:
self.field.wave_type = value
# -------------------------------------------------------------------------
# Wrappers for Independent Field Attributes
# -------------------------------------------------------------------------
@property
def E_ac(self) -> float:
"""Wraps to
:attr:`osaft.core.backgroundfields.BackgroundField.E_ac`
"""
return self.field.E_ac
# -------------------------------------------------------------------------
# Wrappers for Independent Scatterer Attributes
# -------------------------------------------------------------------------
@property
def rho_s(self) -> float:
"""Wraps to :attr:`osaft.core.fluids.InviscidFluid.rho_s`"""
return self.scatterer.rho_f
@rho_s.setter
def rho_s(self, value: float) -> None:
self.scatterer.rho_f = value
@property
def c_s(self) -> float:
"""Wraps to :attr:`osaft.core.fluids.InviscidFluid.c_s`"""
return self.scatterer.c_f
@c_s.setter
def c_s(self, value: float) -> None:
self.scatterer.c_f = value
# -------------------------------------------------------------------------
# Wrappers for Dependent Scatterer Attributes
# -------------------------------------------------------------------------
@property
def kappa_s(self) -> float:
"""Wraps to :attr:`osaft.core.fluids.InviscidFluid.kappa_f`"""
return self.scatterer.kappa_f
# -------------------------------------------------------------------------
# Wrappers for Independent Fluid Attributes
# -------------------------------------------------------------------------
@property
def rho_f(self) -> float:
"""Wraps to :attr:`osaft.core.fluids.ViscousFluid.rho_f`"""
return self.fluid.rho_f
@rho_f.setter
def rho_f(self, value: float) -> None:
self.fluid.rho_f = value
@property
def c_f(self) -> float:
"""Wraps to :attr:`osaft.core.fluids.ViscousFluid.c_f`"""
return self.fluid.c_f
@c_f.setter
def c_f(self, value: float) -> None:
self.fluid.c_f = value
@property
def eta_f(self) -> float:
"""Wraps to :attr:`osaft.core.fluids.ViscousFluid.eta_f`"""
return self.fluid.eta_f
@eta_f.setter
def eta_f(self, value: float) -> None:
self.fluid.eta_f = value
# -------------------------------------------------------------------------
# Wrappers for Dependent Fluid Attributes
# -------------------------------------------------------------------------
@property
def kappa_f(self) -> float:
"""Wraps to :attr:`osaft.core.fluids.ViscousFluid.kappa_f`"""
return self.fluid.kappa_f
@property
def k_f(self) -> complex:
"""Wraps to :attr:`osaft.core.fluids.ViscousFluid.k_f`"""
return self.fluid.k_f
@property
def delta(self):
"""Wraps to :attr:`osaft.core.fluids.ViscousFluid.k_f`"""
return self.fluid.delta
# -------------------------------------------------------------------------
# Dependent Variables Methods
# -------------------------------------------------------------------------
def _compute_f_1(self) -> complex:
return 1 - self.kappa_s / self.kappa_f
def _compute_f_2(self) -> complex:
return (
2
* (1 - self.gamma)
* (self.rho_t - 1)
/ (2 * self.rho_t + 1 - 3 * self.gamma)
)
def _compute_delta_t(self) -> float:
return self.delta / self.R_0
def _compute_gamma(self) -> complex:
return -3 / 2 * (1 + 1j * (1 + self.delta_t)) * self.delta_t
def _compute_kappa_t(self) -> float:
return self.kappa_s / self.kappa_f
def _compute_rho_t(self) -> float:
return self.rho_s / self.rho_f
def _compute_Phi(self) -> float:
return 1 / 3 * self.f_1 + 1 / 2 * self.f_2.real
if __name__ == "__main__":
pass