Fig. 4.

(Colour online) a 3D acoustic radiation force magnitudes ($\left|F_{ac}\right|$, N) on a particle with a radius of 30 µm; b in-plane $\left|F_{ac}\right|$; and c out-of-plane $\left|F_{ac}\right|$ [red arrow in (a)], where the inset shows the directions of the plotted forces above a vibrating antinode. $F_B$ and $F_G$ are the buoyancy and gravity, respectively. The dashed line and the equation in (c) show the exponential fitting of the modelled acoustic radiation force