Mechatronics Engineering Department, Escola Politécnica da Universidade de São Paulo, São Paulo, Brazil.
IEEE Trans Ultrason Ferroelectr Freq Control. 2010;57(2):469-79. doi: 10.1109/TUFFC.2010.1427.
A finite element analysis and a parametric optimization of single-axis acoustic levitators are presented. The finite element method is used to simulate a levitator consisting of a Langevin ultrasonic transducer with a plane radiating surface and a plane reflector. The transducer electrical impedance, the transducer face displacement, and the acoustic radiation potential that acts on small spheres are determined by the finite element method. The numerical electrical impedance is compared with that acquired experimentally by an impedance analyzer, and the predicted displacement is compared with that obtained by a fiber-optic vibration sensor. The numerical acoustic radiation potential is verified experimentally by placing small spheres in the levitator. The same procedure is used to optimize a levitator consisting of a curved reflector and a concave-faced transducer. The numerical results show that the acoustic radiation force in the new levitator is enhanced 604 times compared with the levitator consisting of a plane transducer and a plane reflector. The optimized levitator is able to levitate 3, 2.5-mm diameter steel spheres with a power consumption of only 0.9 W.
本文提出了一种单轴声悬浮装置的有限元分析和参数优化。该有限元方法用于模拟由具有平面辐射面和平整反射器的 Langevin 超声换能器组成的悬浮器。通过有限元方法确定换能器的电阻抗、换能器表面位移以及作用于小球的声辐射势。数值电阻抗与阻抗分析仪获得的实验结果进行了比较，预测的位移与光纤振动传感器获得的位移进行了比较。通过将小球置于悬浮器中，对数值声辐射势进行了实验验证。同样的程序也用于优化由曲面反射器和平凹面换能器组成的悬浮器。数值结果表明，与由平面换能器和平整反射器组成的悬浮器相比，新悬浮器的声辐射力增强了 604 倍。优化后的悬浮器仅需 0.9 W 的功率即可悬浮 3 、 2.5 毫米直径的钢球。
