Acoustic diffraction analysis by the impulse response method: A line impulse response approach

Abstract

Acoustic diffraction of plane impulsive waves is considered for free-field, baffled, and pressure release boundary conditions, in the case of an arbitrary spatial distribution of combined, amplitude-time delay modulation in an aperture. The method is based on the impulse response analysis of parallel aperture lines, the line impulse responses being then integrated to give an aperture impulse response. A closed-form, analytical expression is derived for lines having an arbitrary amplitude modulation. In the case ofnonmodulated apertures of an arbitrary shape, the aperture impulse response is also of an analytical form, directly involving the aperture contour line. The analysis is performed with emphasis on maintaining clear physical sense of successive evaluation steps.

Acoustic beam modeling of ultrasonic transducers and arrays using the impulse response and the discrete representation methods

“…The accuracy of the results depends strongly on the temporal and spatial resolutions used in the model. By considering the three contour cases: rigid baffle, soft baffle and free field, the impulse response function presented by Piwakowski and Delannoy (1989) and based on the work of Lasota et al (1984) is: Equation (11) is more general than Eq. (8), where the factor that takes into account the different cases of boundary was included, as well as the delay function used in the focalization of arrays.…”

Fast Three-dimensional Opto-acoustic Simulation for Linear Array with Rectangular Elements

“…The exact time-domain impulse response for a rectangular element was described by San Emeterio and Ullate (1992) [16]. For a line source, the exact time-domain impulse response is described by Lasota et al (1984) [14]. Scarano et al (1985) [15] proposed an impulse response calculation for rectangular transducer elements that involved a separable aperture function.…”

The calculation of the transient near and far field of a baffled piston using low sampling frequencies

“…1͑a͒. The impulse response function can be calculated analytically for several transducer geometries, 7,8,[10][11][12] for several transducer velocity profiles 13,14 and for curved transducers. 9,15 …”