| With the rapid development of science technology,the high-speed rail, while facilitating human’s life, also introduces noise, especially that caused by vibration, which disturbs us during the run time, into our life. Particle damper, as a sort of damping mode with simple structure, is applied in various occasions due to its excellent vibration damping performance. Therefore, the particle damper is applied in high-speed rail wheels and the characters of its vibration damping are explored in this paper.Diverse vibration damper performance caused by different factors can be explored on the basis of cantilever beam experiment, because what wheels received is a class of wide frequency band incentive. By comparing the variation tendency of test points’ vibration response as well as structural modal damping ratio, such a conclusion can be drawn that some parameters such as particles’ mass ratio, duty ratio, material, diameter and interval number of containers will exert an influence on the damping characteristics, and there always exists an optimum value. Moreover, duty ratio and interval number effect more on the ensemble, and on the contrary, the influence caused by mass ratio is relatively weak.Based on the modal analysis on wheels’ structure by using the ANSYS software, such a conclusion can be drawn that the majority of modals which global noise contribution are relatively greater concentrate in where axial modes as well as radial modes has strongly coupled relationship; that is to say, number of nodal circles of these modals equal to 1 and numbers of nodal diameters of that exceed 1, and then, the conclusion can be verified by using LMS software. Another significant conclusion, the positions of wheels that vibrate intensely caused by external incentive mainly concentrate in tread、flange and the wheel plate, is discovered by the analysis of vibration response. By studying characters effected by changing modal damping ratio as well as simulating particle damping ring, an experimental result cannot be neglected is that the variation of modal damping ratio with middle frequency band can inhibit the structure vibration perfectly. The differential speed regulation and reversing machinery of roller pumping unit developed in this paper has solved the speed regulation and reversing problem that constrained the promotion of roller pumping unit, which laid a solid foundation for its promotion.Inputting the data of wheels vibration from ANSYS software analysis into Virtual.Lab software, exploring characteristic of sound field and combining the analysis of surface acoustic pressure, radiated sound power as well as radiation efficiency, a regulation can be discovered that the vast majority of noise capacity are within the range of 2000Hz~4000Hz; besides, the modals that has greater noise contribution always at this range. According to the analysis of wheels’ plate contribution, an apparent result is that positions inner and outer wheel plates contribute the most noise; however, noise is concentrated in the space where the included angle down from the axis is 30 degrees with reference to the directional analysis.In accordance with previous experiments as well as analysis, damping rings can be designed by using parameters, including composition of particles,ratio and interval number of containers. Besides, the conclusion of wheels’ vibration response and radiated sound pressure verified the optimality of designed parameters; furthermore, the correctness of experiments and theoretical analysis can be affirmed. Finally, compared with the damping effect of existing products, a remarkable finding is that the excesses of radial and axial noise are 1.76 d B and 3.21 d B respectively, and that of wheel is 16 dB. |
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