Acoustic radiation force


Acoustic radiation force is a physical phenomenon resulting from the interaction of an acoustic wave with an obstacle placed along its path. Generally, the force exerted on the obstacle is evaluated by integrating the acoustic radiation pressure over its time-varying surface.
The magnitude of the force exerted by an acoustic plane wave at any given location can be calculated as:
where
The effect of frequency on acoustic radiation force is taken into account via intensity and absorption. As a reference water has an acoustic absorption of 0.002 dB/.
Acoustic radiation forces on compressible particles such as bubbles are also known as Bjerknes forces, and are generated through a different mechanism, which does not require sound absorption or reflection.