Pressure map, delay view and wave animation

How the Fields dialog is calculated.

The Fields dialog shows three views of the selected beam. They share one model: each active element radiates a cylindrical wave, 1/√r in amplitude, delayed by its focal-law delay. Waves cross the wedge/piece interface along the path of least time (Fermat’s principle), so refraction is included.

Pressure map: the magnitude of the coherent sum at each point, in dB below its maximum. The white dashed line is the centre ray and the white dot the focus.

Delay view: the firing delay of each element for the chosen beam, and a matrix of all beams of the beamset.

Aperture: the numerical aperture NA = sinθ of the used aperture seen from each point along the beam, θ = atan((A/2)/r), with the −6 dB spread half-angle as a reference line.

Wave animation: a Gaussian pulse of 60 % fractional bandwidth travelling through the part. Use the slider to scrub or Play to animate.

Back-wall reflection adds the wave reflected once from the bottom surface (method of images, with the free-surface shear reflection coefficient when the beam is a shear wave). Attenuation in dB/mm reduces each path by its length in the part.

These are planning aids, not a full-wave simulation: only one reflection is modelled, with no mode-converted waves, and the interface is treated as flat.

The Pressure map, delay view and wave animation dialog in the workbench — The dialog as it appears in the workbench.

Pressure map, delay view and wave animation

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