focusedAnnulusONeil

Compute axial pressure for focused annulus transducer using O'Neil's solution.

Syntax

p_axial = focusedAnnulusONeil(radius, diameter, amplitude, phase, frequency, sound_speed, density, axial_position)

Description

focusedAnnulusONeil calculates the axial pressure for a focused annulus transducer using O'Neil's solution (O'Neil, H. Theory of focusing radiators. J. Acoust. Soc. Am., 21(5), 516-526, 1949). The annuluar elements are uniformly driven by a continuous wave sinusoid at a given frequency and normal surface velocity.

The solution is evaluated at the positions along the beam axis given by axial_position (where 0 corresponds to the transducer surface).

Note, O'Neil's formulae are derived under the assumptions of the Rayleigh integral, which are valid when the transducer diameter is large compared to both the transducer height and the acoustic wavelength.

Inputs

radius	transducer radius of curvature [m]
diameter	2 x num_elements array containing pairs of inner and outer aperture diameter (diameter of opening) [m]
amplitude	array containing the normal surface velocities for each element [m/s]
phase	array containing the phase for each element [rad]
frequency	driving frequency [Hz]
sound_speed	speed of sound in the propagating medium [m/s]
density	density in the propagating medium [kg/m^3]
axial_position	vector of positions along the beam axis where the pressure amplitude is calculated [m]

Outputs

p_axial

pressure amplitude at the positions specified by axial_position [Pa]

See Also

focusedBowlONeil, mendousse