| Ultrasonic standing wave suspension technology refers to a containerless processing technology that uses the force generated by ultrasonic standing waves to balance the gravity of an object to achieve object suspension and non-contact state.Compared with other suspension technologies,ultrasonic standing wave suspension is paid more attention for its multiple advantages for example the good suspension stability,being not limited by the material of the object,no additional effects on the material,no need to heat the experimental conditions and so on.Researchers at home and abroad continue to conduct research from the perspective of suspension capacity and suspension stability to improve the suspension performance of the standing wave sound field,including the introduction of resonan t tubes.But at present,the introduction of resonant tube is more in the application stage,There is no specific analysis of the influence of the structure of the resonant tube on the suspension performance of the standing wave sound field.In view of this,based on some theoretical knowledge of the standing wave sound field,from the perspective of suspension capacity and suspension st ability this paper analyzes the influence of the resonance tube structure on the standing wave sound field suspension performance.The research work of this article is as follows:First,based on the assumption of ideal conditions,the three basic equation s under small amplitude sound waves are derived.And combined with the basic theory under linear acoustics,the distribution of sound pressure in the plane standing wave sound field is analyzed theoretically.Based on the theoretical method proposed by Kin g and Gor 'Cov,the expression of acoustic radiation force is derived,and the stable suspension position of the object and the stable suspension area in the sound field are analyzed accordingly.Secondly,both the transmitting end and the reflecting end ar e designed as concave spherical surfaces,and the acoustic suspension simulation model without the resonan t tube is established.The modal analysis of the resonan t-free tube mode is used to determine the sound wave excitation frequency that can generate a fairly strong sound standing wave field.And the standing wave theory is used to verify the validity of the simulation model when the reflection end and the emission end are both flat.Then,a single-axis suspension system was built to verify the feasibili ty of the simulation model when the transmitting end and the reflecting end were concave spherical surfaces from an experimental perspective.A simple cylindrical resonant tube is introduced to establish a corresponding simulation model,and the sound pres sure distribution on the central axis of the resonant tube under different radius sizes is discussed.And compared with the working condition without resonan t tube,the results show that a simple cylindrical resonant tube within the size range can effectiv ely improve the suspension capacity of the standing wave sound field.Finally,based on the obtained simulation results,the type of Bezier Curve resonant tube is introduced.And modal analysis and calculation of concave and convex models.Considering the opening diameter size of Bezier Curve resonance t tube at the same time,the influence characteristics of Bezier Curve resonan t tube with different structures on the suspension performance of standing wave acoustic field are compared and analyzed.The results show that the introduction of the Bezier Curve type resonan t tube can significantly improve the suspension performance of the sound field.The two types of concave and convex models have improved the suspension performance of the standing wave sound field,and the improvement effect of the concave model structure is more obvious.However,the structure of the cylindrical resonan t tube is simpler.Accordingly,a reasonable choice can be made for the shape and size of the resonant tube according to different requirements. |
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