1887
banner image
No data available.
Please log in to see this content.
You have no subscription access to this content.
No metrics data to plot.
The attempt to load metrics for this article has failed.
The attempt to plot a graph for these metrics has failed.
Acoustic characterization of panel materials under simulated ocean conditions using a parametric array source
Rent:
Rent this article for
USD
10.1121/1.2945119
/content/asa/journal/jasa/124/2/10.1121/1.2945119
http://aip.metastore.ingenta.com/content/asa/journal/jasa/124/2/10.1121/1.2945119

Figures

Image of FIG. 1.
FIG. 1.

Drive wave forms for the parametric array showing the ideal form of the demodulated signal.

Image of FIG. 2.
FIG. 2.

Difference frequency spectra obtained using raised cosine bell modulated pulses with envelope frequencies of 20, 10, 5, and . The amplitudes are normalized to the maximum of the spectra.

Image of FIG. 3.
FIG. 3.

Difference frequency beam profiles for frequencies of 5, 10, 20, and at a range of from the transducer for an array truncated at from the transducer.

Image of FIG. 4.
FIG. 4.

Variation of generated difference frequency pulse amplitude as a function of hydrostatic pressure through two hydrostatic pressure cycles at for pulse center frequencies of 5 and . The sequence of results moves clockwise around the hysteresis loops as the pressure is varied, with the two upper lines representing the rising pressure phase and the two lower lines representing the falling pressure phase.

Image of FIG. 5.
FIG. 5.

Schematic diagram of the parametric array in APV showing the location of the transducer, acoustic filter, test panel, and hydrophones (all dimensions in meters). Note that both receiving hydrophones are depicted, although only one is used at a time. The diagram is drawn to scale.

Image of FIG. 6.
FIG. 6.

Examples of received hydrophone signals for a measurement of reflection loss. The wave forms shown were recorded for a pulse modulation frequency of . Top: signal with test panel present; center: reference signal with test panel absent; bottom: the signal obtained by subtracting the two signals, showing the reflected signal only.

Image of FIG. 7.
FIG. 7.

Results obtained for reflection loss measurements for test objects 1 and 2 at ambient pressure and . (a) Results for test object 1 (steel plates separated by ) using and (b) results for test object 2 (PMMA plates separated by ) using .

Image of FIG. 8.
FIG. 8.

Model predictions for test panel 1 at three values of hydrostatic pressure. (a) Reflection loss values calculated for and (b) transmission loss values for .

Image of FIG. 9.
FIG. 9.

Measured results for test panel 1 at three values of hydrostatic pressure using a pulse envelope. (a) Reflection loss was measured at , whereas (b) transmission loss was measured at .

Image of FIG. 10.
FIG. 10.

Model predictions for (a) reflection loss and (b) transmission loss of test panel 2 at for three values of hydrostatic pressure.

Image of FIG. 11.
FIG. 11.

Measured results for test panel 2 at and three values of hydrostatic pressure. (a) Reflection loss was measured with a pulse generated using , whereas (b) transmission loss was measured with a pulse generated using .

Image of FIG. 12.
FIG. 12.

Results for test panel 1 at and ambient pressure for pulses generated using envelope frequencies of 5, 10, 20, and showing agreement between frequency ranges.

Image of FIG. 13.
FIG. 13.

Results for reflection loss of test panel 1 (left) at a pressure of and a temperature of and for test panel 2 at a pressure of and a temperature of . For panel 1, the measurement window was varied from in steps of ; for panel 2, it was varied from in steps of . The mean values of the calculated results are shown with the error bars calculated for a confidence level of 95%.

Tables

Generic image for table
TABLE I.

Test objects used to exercise the method.

Loading

Article metrics loading...

/content/asa/journal/jasa/124/2/10.1121/1.2945119
2008-08-01
2014-04-18
Loading

Full text loading...

This is a required field
Please enter a valid email address
752b84549af89a08dbdd7fdb8b9568b5 journal.articlezxybnytfddd
Scitation: Acoustic characterization of panel materials under simulated ocean conditions using a parametric array source
http://aip.metastore.ingenta.com/content/asa/journal/jasa/124/2/10.1121/1.2945119
10.1121/1.2945119
SEARCH_EXPAND_ITEM