Quantitative Analysis of Secondary Bjerknes Forces in Various Liquids

Evaluating numerically the interaction forces between two free bubbles, under the action of a background of random acoustic radiation, we highlight the contributions of coefficients and to the magnitude of these forces. The quantitative study of the forces is done for several fluids, as different as possible in terms of properties: water, mercury, liquid helium, and superfluid helium. These forces are evaluated, for different radii of the oscillating bubbles, = ⎡10 − 10 ⏋ m, that the scattering–absorption forces and the scattering–scattering forces are close in magnitude. For water, mercury and liquid helium, the force ratio is in the range ∈ (10 −1). For superfluid helium, the forces change direction, oscillating, and the ratio of the forces is much less than one, | | 1.