Sphere scattering of nonlinearly interacting acoustic waves

Abbasov, Iftikhar B.; Zagrai, N. P.

doi:10.1007/bf02029824

Cited by 6 publications

(4 citation statements)

References 2 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Moreover, difference-frequency generation in scattering of two collinear plane waves by means of a sphere was previously studied [25]. However, the results obtained in this study show that the difference-frequency scattered pressure has singularities in the polar angle of spherical coordinates (i.e.…”

Section: Introductionmentioning

confidence: 70%

“…It is worthy to relate our analysis with a previous theoretical study on difference-frequency generation in acoustic scattering [25]. We have tried to draw a direct comparison between this work and the method presented here.…”

Section: Resultsmentioning

confidence: 97%

“…The directive pattern in the xz-plane of the difference-frequency scattered pressure given in Eq (25). and produced by two collinear plane waves (θ 2 = 0) are shown in Fig.…”

mentioning

confidence: 99%

See 2 more Smart Citations

Difference-frequency generation in nonlinear scattering of acoustic waves by a rigid sphere

Silva

Bandeira

2013

Ultrasonics

View full text Add to dashboard Cite

In this paper, the partial-wave expansion method is applied to describe the difference-frequency pressure generated in a nonlinear scattering of two acoustic waves with an arbitrary wavefront by means of a rigid sphere. Particularly, the difference-frequency generation is analyzed in the nonlinear scattering with a spherical scatterer involving two intersecting plane waves in the following configurations: collinear, crossing at right angles, and counter-propagating. For the sake of simplicity, the plane waves are assumed to be spatially located in a spherical region which diameter is smaller than the difference-frequency wavelength. Such arrangements can be experimentally accomplished in vibro-acoustography and nonlinear acoustic tomography techniques. It turns out to be that when the sphere radius is of the order of the primary wavelengths, and the downshift ratio (i.e. the ratio between the fundamental frequency and the difference-frequency) is larger than five, difference-frequency generation is mostly due to a nonlinear interaction between the primary scattered waves. The exception to this is the collinear scattering for which the nonlinear interaction of the primary incident waves is also relevant. In addition, the difference-frequency scattered pressure in all scattering configurations decays as r(-1)lnr and 1/r, where r is the radial distance from the scatterer to the observation point.

show abstract

Section: Introductionmentioning

confidence: 70%

Section: Resultsmentioning

confidence: 97%

See 1 more Smart Citation

Difference-frequency generation in nonlinear scattering of acoustic waves by a rigid sphere

Silva

Bandeira

2013

Ultrasonics

View full text Add to dashboard Cite

show abstract

“…One of the earlier studies realized for the nonlinear interaction of two scattered waves can be found in Dean-III (1962). In a more recent work, the scattering of two plane waves by a rigid sphere was investigated (Abbasov and Zagrai 1994). However, both investigations considered only the monopole modes for the primary scattered waves.…”

Section: Introductionmentioning

confidence: 99%

Difference-frequency generation in vibro-acoustography

Silva

Mitri

2011

Phys. Med. Biol.

View full text Add to dashboard Cite

Vibro-acoustography (VA) is a medical imaging method based on the nonlinear interaction of two or more distinct ultrasound beams whose frequencies differ by several kHz. In turn, the interacting waves produce a difference-frequency signal which carries the information of the imaged tissue region. Two mechanisms are responsible for the difference-frequency generation (DFG) in VA, namely the dynamic (oscillatory) radiation force and the scattering of sound-by-sound. The role and importance of each phenomenon in VA is assessed here. A theoretical model based on Westervelt's equation for the DFG in the nonlinear scattering of two incident ultrasound waves by a small rigid sphere (compared to the incident wavelengths) is presented. Furthermore, a scattering experiment using VA is devised and the data show very good agreement with the proposed theory. The results reveal that the effect of scattering of sound-by-sound is the dominant component in the DFG in VA rather than the dynamic radiation force.

show abstract

References

2016

Hydroacoustic Ocean Exploration

View full text Add to dashboard Cite

Sphere scattering of nonlinearly interacting acoustic waves

Cited by 6 publications

References 2 publications

Difference-frequency generation in nonlinear scattering of acoustic waves by a rigid sphere

Difference-frequency generation in nonlinear scattering of acoustic waves by a rigid sphere

Difference-frequency generation in vibro-acoustography

References

Contact Info

Product

Resources

About