The structure of radiation forces in a viscous fluid layer on an elastic half-space and the acoustic flows generated by them

The field of a surface acoustic wave in the system "viscous fluid layer - elastic substrate" is calculated taking into account the shear components in the fluid. The dispersion equation was used to calculate the amplitudes of the surface wave. The radiation pressure arising in a viscous fluid from the side of a standing surface wave and acting on an element of its volume due to the nonlinearity of the equations of motion, and the acoustic flows created by it are calculated. It is shown that taking viscosity into account changes the spatial distribution of radiation pressure. Attenuation of the wave causes an additional tendency for the collection of suspended particles in the center of the system. Shear components lead to significant gradients of radiation pressure near the interface between the media. They play a decisive role in the formation of ordered ensembles of suspended particles at the last stage of the self-organization process.