Research On Non-contact Ultrasonic Supporting And Driving Method

It is necessary to avoid minute defects such as surface crack and scratch during the manufacture of high-precision products such as large integrated circuits and semiconductor components.The minute defects of products are usually caused by contacting during the processing,handling and packaging,and non-contact operation technology becomes one of effective methods to solve this kind of problem.The technology of non-contact ultrasonic supporting and driving has broad application prospects in materials science,biochemical analysis and other fields,as well as in the processing and directional transportation of highprecision mechanical products and high-purity medicines.It is of great engineering application value and theoretical significance to conduct a series of mechanism and experimental studies on the non-contact ultrasonic supporting and driving method of the target object.In this thesis,polystyrene beads and various liquids are realized to be stably suspended in the air based on the mechanism of non-contact standing wave ultrasonic supporting.Secondly,we researched on the scheme non-contact ultrasonic driving in the pipeline and its basic principle.The polystyrene beads and droplets are directionally transmitted in the pipeline over a long distance.And then,we study and analyzed the mechanism of non-contact near-field ultrasonic driving,and verified the feasibility of non-contact directional transportation of flat objects through experiments.In the last part of this thesis,a scheme non-contact waveguide ultrasonic driving which realized the non-contact transport of polystyrene beads and absolute fluid particles in the air domain is proposed by combining the advantages of both non-contact standing wave ultrasonic supporting and non-contact near-field ultrasonic driving.The main research works of this thesis are as follows:The mechanism and experimental study of non-contact standing wave ultrasonic supporting.The formation principle of ultrasonic standing wave was summarized,and the basic principle of non-contact standing wave ultrasonic supporting was expounded.An experimental device was designed and constructed for experimental research on the stably suspension of various types of target objects in the standing wave sound field and the ultrasonic autonomous coalescence of atomized water particles.The finite element simulation analysis of standing wave sound field and the phenomenon of ultrasonic autonomous coalescence were carried out based on COMSOL platform.The mechanism and experimental research on non-contact ultrasonic driving in the pipeline.The pipeline of one dimensional wave equation and the acoustic field in the pipeline were deduced and established based on the conservation equations of mass and momentum of fluid medium volume element in the pipeline.This thesis expounded the basic principle of noncontact pipeline ultrasonic driving.An experimental device was designed and built to carry out an experimental study on directional transportation over a long distance of the solid spheres and droplets in the pipeline.The finite element simulation analysis of pipeline sound field and droplet movement were carried out based on COMSOL platform.The mechanism and experimental research on non-contact near-field ultrasonic driving.The basic principle of non-contact near-field ultrasonic driving was revealed.The traveling wave excited on the vibrating plate is derived according to the wave equation.Based on the theory of Minikes-Bucher,we researched the vertical supporting force and horizontal driving force acting on the driving plate.We designed the structure size of the vibrating plate and based on ANSYS platform obtained the best excitation frequency of the entire experimental system by modal analysis.Finally,an experimental device was built for the research on the non-contact directional transportation of flat objects.The mechanism and experimental research on non-contact waveguide ultrasonic driving.This thesis elaborated the basic principles of non-contact waveguide ultrasonic driving by combining standing wave ultrasonic supporting mechanism and near-field ultrasonic driving mechanism.Experimental devices were built for experimental research on non-contact directional transportation controllable ultrasonic driving of target objects.The finite element simulation analysis of waveguide sound field and the phenomenon of non-contact ultrasonic driving and autonomous coalescence were carried out based on COMSOL platform.