Nonlinear trapping stiffness of mid-air single-axis acoustic levitators
Nonlinear trapping stiffness of mid-air single-axis acoustic levitators
复制标题
DOI：
10.1063/1.5034116
复制
发表时间：
2018-07-16
影响因子：
4
通讯作者：
Drinkwater, B. W.
中科院分区：
文献类型：
--
作者：
Fushimi, T.;Hil, T. L.;Drinkwater, B. W.
我们描述和实验探索的非线性刚度模型的捕获的固体颗粒在单轴声悬浮器。与通常采用的线性刚度假设相反，我们的非线性模型准确地预测了系统的响应。我们的非线性模型近似的声场附近的陷阱作为一个一维的正弦曲线，并解决了所产生的动态使用数值延拓。特别是，我们预测软化的刚度与振幅以及倍周期分叉，即使是小的激励振幅约为2%的波长。这些非线性动态特性的实验观察到在一个单轴悬浮器工作在40 kHz和捕获毫米级的发泡聚苯乙烯球。观察到的和预测的行为之间的极好的协议，这表明这个相对简单的模型捕捉相关的物理现象。这种新模型能够准确预测被捕获粒子的动态不稳定性，从而有利于非接触式运输和操纵应用。出版社：AIP Publishing
We describe and experimentally explore a nonlinear stiffness model of the trapping of a solid particle in a single-axis acoustic levitator. In contrast to the commonly employed linear stiffness assumption, our nonlinear model accurately predicts the response of the system. Our nonlinear model approximates the acoustic field in the vicinity of the trap as a one-dimensional sinusoid and solves the resulting dynamics using numerical continuation. In particular, we predict a softening of stiffness with amplitude as well as period-doubling bifurcations, even for small excitation amplitudes of approximate to 2% of the wavelength. These nonlinear dynamic features are observed experimentally in a single-axis levitator operating at 40 kHz and trapping millimetre-scale expanded polystyrene spheres. Excellent agreement between the observed and predicted behaviour is obtained suggesting that this relatively simple model captures the relevant physical phenomena. This new model enables the dynamic instabilities of trapped particles to be accurately predicted, thereby benefiting contactless transportation and manipulation applications. Published by AIP Publishing.