Acoustic radiation force on a spherical particle in a fluid-filled cavity

The acoustic pressure and radiation force acting on the spherical rigid particle located in a fluid-filled cylindrical vessel are determined as a function of the primary wave frequency making use of the solution of a problem of plane harmonic wave scattering on a spherical body. The problem is solved by the variables separation method. To satisfy the boundary conditions on cylindrical and spherical surfaces, the mutual expansions of spherical wave functions over the cylindrical ones and vice versa are used. Required constants in the solution are calculated from an infinite system of algebraic equations which is solved by a truncation method. It is established that the value of the radiation force is affected significantly by the presence of the cylindrical boundary surface. Depending on the frequency of the incident wave, the radiation force can change its direction. It is established that there are peak values of the force at some discrete values of the frequency. The mentioned peculiarities can stipulate specific localization effects and influence the motion of the particles in the cylindrical cavity under the influence of an acoustic wave. (C) 2012 Acoustical Society of America. [http://dx.doi.org/10.1121/1.4739440]