Study On Single Beam Acoustic Tweezers

With the rapid development of modern science and technology,the application of high frequency ultrasound in the fields of scientific research and industry,such as ultrasonic medical testing and ultrasonic nondestructive detection,is becoming mature.Acoustic radiation force(ARF)can help realizing the functions in biomedical field such as cell screening,drug delivery,and non-contact manipulating in industrial area,which is a research hotspot.It’s of practical significance for late-model acoustic tweezers design to study ARF on spherical particles.This paper mainly studies the ARF characteristics of the spherical particles with method of acoustic scattering theory of sound wave.In chapter one,we review the history of theoretical research and practical application of ARF and introduce lately research progress of radiation force.Then,the calculation method is delivered based on spherical acoustic scattering theory.In chapter two,we introduce the ARF induced by middle hollow focusing transducer on spherical particles with point source acoustic scatting.Without considering acoustic attenuation,simulations show that there are pulling forces zones in the near field of transducer,which is relevant with outer angle,inner angle and spherical radius.The results may help to design acoustic tweezers in the future.In chapter three,we introduce the ARF induced by middle hollow piston transducer on spherical particles with point source acoustic scatting.Without considering acoustic attenuation,simulations show that there are pulling forces zones in the near field of transducer,which is relevant with spherical particle’s size and material,outer radius,inner radius and distance,which will guide the realization of new acoustic tweezers.In chapter four,with finite series-expansion theory,we calculated the beam coefficients of zero-order Bessel-gauss beam.Then,the ARF on spherical particles caused by zero-order Bessel-gauss beam in the axis is calculated.The results widen the theoretical research on ARF of Bessel beam,which provides support for acoustic capture with single non-diffraction beam.In this paper,different kinds of acoustic radiation models are given,ARF is calculated with some single beams,which delivers theoretical guidance for industrial non-destructive control and cellular medicine drug screening.