چكيده به لاتين
We propose a simple, practical and versatile acoustic driven swimmer, composed of two spherical bodies which may radiate the sound field, monochromatically, at monopole state (breathing mode of vibration) and are linked by a rigid rod. Considering the nonlinear acoustic effects, the net acoustic radiation force exerted on the device is analytically derived and the surprising non-zero states are approved. Two different configurations are considered: In the first, both spheres radiate and the second, one of the spheres is off which may serve as a classic container. In both cases, the full manipulability conditions of swimmers are obtained and the effects of size factors, frequency of operation etc., are discussed. Considering hydrodynamics effects assuming low Reynolds number swimming condition, the frequency-dependant swimming velocity is obtained via the so-called reflection method and the optimal radiating states are discussed. Finally, the challenge of random walk due to host medium fluctuations is discussed and it is shown that the proper design may overcome the ubiquity of Brownian motion. The novel methodology will open a new path toward the self-propulsive controllable devices which may play the role of carriers, machines or mechanisms at small-scales.
