金属波纹管隔振特性的研究

发布时间：2018-06-17 06:15

本文选题：金属波纹管 + 激振频率　；参考：《河南科技大学》2013年硕士论文

【摘要】：金属波纹管是一类圆柱形薄壁的弹性壳体，其横向带有波纹，在管路系统中主要起到减振降噪的作用。在实际工况中，为了提高金属波纹管的减振降噪效果，需要对其隔振特性进行研究。本文以DN219金属波纹管为对象，采用数值仿真和试验相结合的方法进行研究。利用ANSYS有限元分析软件建立了金属波纹管的有限元模型，，研究几何参数、结构构型及阻尼材料特性对金属波纹管减振效果的影响，最后通过试验对模型进行验证。仿真结果表明：当激振频率为40Hz时，该金属波纹管的减振效果随着波高及波数的增加而增大，随着波距、壁厚、直径及阻尼材料的弹性模量的增加而减小，随着阻尼材料的厚度的增加先增大后减小；当激振频率为13.5Hz时，该金属波纹管的减振效果随着波高、波距、壁厚、直径、波数及阻尼材料的弹性模量的增加先减小后增大。金属波纹管减振效果与阻尼材料薄厚的关系比较复杂。当阻尼材料厚度小于0.1mm时，随着阻尼材料厚度的增加而减小，阻尼材料厚度大于0.1mm小于0.2mm时，随着阻尼材料厚度的增加而增大，阻尼材料厚度大于0.2mm小于0.3mm时，随着阻尼材料厚度的增加而减小，阻尼材料厚度大于0.3mm时，随着阻尼材料厚度的增加而增大；当激振频率为5Hz时，该金属波纹管的减振效果随着波高及波数的增加而减小，随着波距、壁厚、直径及阻尼材料的弹性模量的增加而增大，随着阻尼材料的厚度的增加先减小后增大。接着对DN219金属波纹管进行振动试验研究，将试验得到的结果和有限元分析的结果进行对比，得知两者之差在工程上可接受的范围之内，从而验证了有限元模型的正确性。本文研究结果对金属波纹管的设计具有一定的参考价值。本文还对DN550金属波纹管进行了试验研究，分别采用负脉冲法和锤击法对无粘性阻尼金属波纹管进行自由振动试验，比较两者的激振效果得知，锤击法虽然试验方便、花费少，但其能量有限且不易控制，对于轻型结构系统可以采用，对大型高刚度的挠性接管就不宜采用；而负脉冲法能够较稳定地输入冲击能量，可以充分激发出所关注的共振频率。当层与层之间加入粘性阻尼材料以后，动态刚度和阻尼系数降低，这主要是由于挠性接管层间摩擦阻尼大于粘性材料的阻尼；试验还表明层间粘性阻尼材料可有效衰减高频振动。
[Abstract]:Metal corrugated tube is a kind of cylindrical thin-walled elastic shell with transverse corrugation, which plays an important role in reducing vibration and noise in pipeline system. In order to improve the vibration and noise reduction effect of metal bellows, the vibration isolation characteristics of metal bellows need to be studied. In this paper, DN219 metal bellows are studied by numerical simulation and experiment. The finite element model of metal bellows is established by using ANSYS finite element analysis software. The effects of geometric parameters, structural configuration and damping material characteristics on the damping effect of metal bellows are studied. Finally, the model is verified by experiments. The simulation results show that when the exciting frequency is 40 Hz, the damping effect of the metal corrugated tube increases with the increase of wave height and wave number, and decreases with the increase of wave distance, wall thickness, diameter and elastic modulus of damping material. With the increase of damping material thickness, the damping effect of the metal corrugated tube first increases and then decreases with the increase of wave height, wave distance, wall thickness, diameter, wave-number and elastic modulus of damping material when the exciting frequency is 13.5 Hz, and then increases with the increase of wave height, wave distance, wall thickness, wave number and elastic modulus of damping material. The relation between the damping effect of metal bellows and the thickness of damping material is complex. When the thickness of damping material is less than 0.1mm, the thickness of damping material decreases with the increase of thickness of damping material. When the thickness of damping material is greater than 0.1mm less than 0.2mm, the thickness of damping material increases with the increase of thickness of damping material, and when the thickness of damping material is greater than that of 0.2mm, the thickness of damping material is smaller than 0.3mm. When the damping material thickness is greater than 0.3mm, the damping material thickness increases with the increase of damping material thickness, and the damping effect of the metal bellows decreases with the increase of wave height and wave number when the exciting frequency is 5 Hz. With the increase of wave distance, wall thickness, diameter and elastic modulus of damping materials, the thickness of damping materials decreases first and then increases. Then the vibration test of DN219 metal bellows is carried out, and the results obtained from the test are compared with the results of finite element analysis, and the difference between the two is found to be within an acceptable range in engineering, which verifies the correctness of the finite element model. The results of this paper have some reference value for the design of metal bellows. The experiments of DN550 metal bellows are also carried out in this paper. The free vibration tests of non-viscous damped metal bellows are carried out by using negative pulse method and hammering method, respectively. The results show that the hammering method is convenient in test and less in cost. However, its energy is limited and difficult to control, so it can be used for light structure system, but not for large flexible nozzle with high stiffness, while the negative pulse method can input shock energy stably, which can fully excite the resonance frequency concerned. When viscous damping material is added between layers, the dynamic stiffness and damping coefficient decrease, which is mainly due to the fact that the friction damping between the flexible pipes is larger than that of the viscous material. The experiment also shows that the interlayer viscous damping material can effectively attenuate the high frequency vibration.
【学位授予单位】：河南科技大学
【学位级别】：硕士
【学位授予年份】：2013
【分类号】：TB535

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