Source code for osaft.solutions.doinikov1994compressible.coefficientmatrix

from __future__ import annotations

import numpy as np

from osaft.core.backgroundfields import WaveType
from osaft.core.frequency import Frequency
from osaft.core.functions import BesselFunctions as Bf
from osaft.core.geometries import Sphere
from osaft.core.variable import ActiveListVariable, ActiveVariable
from osaft.solutions.doinikov1994compressible.base import (
    BaseDoinikov1994Compressible,
)

NDArray = np.ndarray


[docs]class CoefficientMatrix(BaseDoinikov1994Compressible): """Coefficient Matrix Doinikov (viscous fluid-viscous sphere; 1994) :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 in the sphere [m/s] :param eta_s: shear viscosity of in the sphere [Pa s] :param zeta_s: bulk viscosity of in the sphere [Pa 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: shear viscosity [Pa s] :param zeta_f: bulk viscosity [Pa s] :param p_0: Pressure amplitude of the field [Pa] :param position: Position within the standing wave field [m] :param wave_type: Type of wave, traveling or standing """ def __init__( self, f: Frequency | float | int, R_0: Sphere | float | int, rho_s: float, c_s: float, eta_s: float, zeta_s: float, rho_f: float, c_f: float, eta_f: float, zeta_f: float, p_0: float, wave_type: WaveType, position: float, ) -> None: # init of parent method super().__init__( f=f, R_0=R_0, rho_s=rho_s, c_s=c_s, eta_s=eta_s, zeta_s=zeta_s, rho_f=rho_f, c_f=c_f, eta_f=eta_f, zeta_f=zeta_f, p_0=p_0, wave_type=wave_type, position=position, ) # Dependent Variables self._x_hat = ActiveVariable(self._compute_x_hat, "x_hat") self._x_hat_v = ActiveVariable(self._compute_x_hat_v, "x_v hat") self._list_matrix_M_n = ActiveListVariable( self._compute_matrix_M_n, "Matrices M(n)", ) self._list_vector_N_n = ActiveListVariable( self._compute_vector_N_n, "Vectors N(n)", ) self._x_hat.is_computed_by( self.scatterer._k_f, self.sphere._R_0, ) self._x_hat_v.is_computed_by( self.scatterer._k_v, self.sphere._R_0, ) self._list_matrix_M_n.is_computed_by( self._x, self._x_v, self._x_hat, self._x_hat_v, self.frequency._omega, self.fluid._c_f, self.scatterer._c_f, self.fluid._rho_f, self.scatterer._rho_f, self.fluid._eta_f, self.scatterer._eta_f, self.fluid._zeta_f, self.scatterer._zeta_f, ) self._list_vector_N_n.is_computed_by( self._x, self.frequency._omega, self.fluid._c_f, self.fluid._rho_f, self.fluid._eta_f, self.fluid._zeta_f, )
[docs] def det_M_n(self, n: int, column: None | int = None) -> complex: """Determinant of the matrix `M` for the mode `n` :param n: mode :param column: the `l`th coefficient is replaced with the vector `N` """ matrix = self.M(n).copy() vector = self.N(n) if column is not None: matrix[:, column] = vector return np.linalg.det(matrix)
[docs] def M(self, n: int) -> NDArray: """Matrix M of order `n` :param n: order """ return self._list_matrix_M_n.item(n)
[docs] def N(self, n: int) -> NDArray: """Vector `N`""" return self._list_vector_N_n.item(n)
# ------------------------------------------------------------------------- # Properties # ------------------------------------------------------------------------- @property def x_hat(self) -> complex: """Product of :attr:`~.k_s` and :attr:`~.R_0` :math:`\\hat{x}=k_s R_0` """ return self._x_hat.value def _compute_x_hat(self) -> complex: return self.k_s * self.R_0 @property def x_hat_v(self) -> complex: """Product of :attr:`~.k_vs` and :attr:`~.R_0` :math:`\\hat{x}_v=\\hat{k}_s R_0` """ return self._x_hat_v.value def _compute_x_hat_v(self) -> complex: return self.k_vs * self.R_0 # ------------------------------------------------------------------------- # Vector N(n) # ------------------------------------------------------------------------- def _compute_vector_N_n(self, n: int) -> NDArray: vector = np.zeros(4, dtype=complex) vector[0] = -self.x * Bf.d1_besselj(n, self.x) vector[1] = -Bf.besselj(n, self.x) vector[2] = 1j * self.rho_f * self.c_f**2 / self.omega vector[2] += self.zeta_f vector[2] -= 2 / 3 * self.eta_f vector[2] *= Bf.besselj(n, self.x) vector[2] -= 2 * self.eta_f * Bf.d2_besselj(n, self.x) vector[2] *= self.x**2 vector[3] = Bf.besselj(n, self.x) vector[3] -= self.x * Bf.d1_besselj(n, self.x) vector[3] *= 2 * self.eta_f return vector # ----------------------------------------------------------------------- # Matrix M(n) # ----------------------------------------------------------------------- def _compute_matrix_M_n(self, n: int) -> NDArray: # Initialize matrix matrix = np.zeros((4, 4), dtype=complex) # First row matrix[0, 0] = self.x * Bf.d1_hankelh1(n, self.x) matrix[0, 1] = -n * (n + 1) * Bf.hankelh1(n, self.x_v) matrix[0, 2] = -self.x_hat * Bf.d1_besselj(n, self.x_hat) matrix[0, 3] = n * (n + 1) * Bf.besselj(n, self.x_hat_v) # Second Row matrix[1, 0] = Bf.hankelh1(n, self.x) matrix[1, 1] = -Bf.hankelh1(n, self.x_v) matrix[1, 1] -= self.x_v * Bf.d1_hankelh1(n, self.x_v) matrix[1, 2] = -Bf.besselj(n, self.x_hat) matrix[1, 3] = Bf.besselj(n, self.x_hat_v) matrix[1, 3] += self.x_hat_v * Bf.d1_besselj(n, self.x_hat_v) # Third row matrix[2, 0] = 1j * self.rho_f * self.c_f**2 / self.omega matrix[2, 0] += self.zeta_f matrix[2, 0] -= 2 / 3 * self.eta_f matrix[2, 0] *= -Bf.hankelh1(n, self.x) matrix[2, 0] += 2 * self.eta_f * Bf.d2_hankelh1(n, self.x) matrix[2, 0] *= self.x**2 matrix[2, 1] = Bf.hankelh1(n, self.x_v) matrix[2, 1] -= self.x_v * Bf.d1_hankelh1(n, self.x_v) matrix[2, 1] *= 2 * n * (n + 1) * self.eta_f matrix[2, 2] = 1j * self.rho_s * self.c_s**2 / self.omega matrix[2, 2] += self.zeta_s matrix[2, 2] -= 2 / 3 * self.eta_s matrix[2, 2] *= Bf.besselj(n, self.x_hat) matrix[2, 2] -= 2 * self.eta_s * Bf.d2_besselj(n, self.x_hat) matrix[2, 2] *= self.x_hat**2 matrix[2, 3] = self.x_hat_v * Bf.d1_besselj(n, self.x_hat_v) matrix[2, 3] -= Bf.besselj(n, self.x_hat_v) matrix[2, 3] *= 2 * n * (n + 1) * self.eta_s # Fourth row matrix[3, 0] = self.x * Bf.d1_hankelh1(n, self.x) matrix[3, 0] -= Bf.hankelh1(n, self.x) matrix[3, 0] *= 2 * self.eta_f matrix[3, 1] = self.x_v**2 * Bf.d2_hankelh1(n, self.x_v) matrix[3, 1] += (n**2 + n - 2) * Bf.hankelh1(n, self.x_v) matrix[3, 1] *= -self.eta_f matrix[3, 2] = Bf.besselj(n, self.x_hat) matrix[3, 2] -= self.x_hat * Bf.d1_besselj(n, self.x_hat) matrix[3, 2] *= 2 * self.eta_s matrix[3, 3] = self.x_hat_v**2 * Bf.d2_besselj(n, self.x_hat_v) matrix[3, 3] += (n**2 + n - 2) * Bf.besselj(n, self.x_hat_v) matrix[3, 3] *= self.eta_s return matrix
if __name__ == "__main__": pass