双凹面聚焦超声波场中悬浮粒子操控原理与实验仿真

The Mechanism and Simulation of Suspended Particle Manipulation in a Double Concave Focused Ultrasonic Field

为提高聚焦超声波场的悬浮能力以及拓宽悬浮粒子的移动区域,研究了超声波场中声压大小的计算公式以及凹球面阵列中阵元的延迟时间与聚焦点位置的关系式,并运用COMSOL多物理场软件进行仿真验证.通过搭建双凹球面超声波阵列悬浮装置,控制发射极信号相位实现了悬浮粒子在竖直方向上的移动,实验中粒子的运动轨迹与仿真结果有较好的一致性.结果表明:双凹球面超声波阵列声场声压更强、聚焦性更好,且可通过对阵元相位信号的控制实现悬浮粒子在二维平面的移动.

In order to improve the suspension ability of focused ultrasonic field and broaden the moving area of suspended particles,the calculation formula of sound pressure in the ultrasonic field and the relation between the delay time of array elements and the focus position in concave spherical array were studied.COMSOL multiphysics was used for simulation verification.By building a levitation device for the concave spherical ultrasonic array,the phase of emitter signal was controlled to realize the movement of suspended particles in the vertical direction.The particle motion trajectory in the experiment was in good agreement with that in the simulation experiment.The results showed that the double concave spherical ultrasonic array had stronger sound pressure and better focusing ability and the motion of the suspended particles in the two-dimensional plane could be realized with phase signal control.