Simulation of low frequency ultrasonic dual-atomization nozzle′s levitation process
Gao Jianmin1,2, Li Yangbo1
(1.Key Laboratory of Modern Agricultural Equipment and Technology, Ministry of Education & Jiangsu Province, Jiangsu University, Zhenjiang, Jiangsu 212013, China; 2.United States Department of Agriculture Research Service, OH 44691,USA）
Abstract：Researching the levitation to provide a theoretical basis for the second atomization and design guidelines, the finite element method was used, the 3D finite element model of the whole ultrasonic levitation system was built; the nozzle′s vibration frequency was 28 kHz,and its amplitude is 5 μm.Based on ultrasonic-structural coupled theory, the solution was carried out by the explicit dynamics software LS-DYNA; the motion states of the metal ball in the suspension was analyzed; obtaining the displacement, velocity, acceleration of the up and down movement and the angular velocity and angular acceleration. The results of numerical simulation show that the sound field is unstable when the low-frequency ultrasonic nozzle is vibrating; the acoustic radiation force generated by nozzle vibrates can suspend the metal ball to move up and down, and during the up and down movement, the metal ball also had a rotation around its centroid. The dynamics parameters of the ball suspended in the air are obtained through simulation compute, help to design the nozzle.
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