Dynamic Modeling of Metal Diaphragm Coupling Contact Surface and Its Vibration Characteristic Analysis
In order to explore the dynamic equivalent modeling of multi-layer joints of multi-bolt joints such as metal diaphragm couplings,two modeling methods based on virtual material layer to simulate bol-ted joints were proposed.The virtual material parameters were obtained by Hertz contact theory and frac-tal geometry theory.The influence law of the structural parameters of the diaphragm group on the axial vi-bration transmission characteristics of the whole diaphragm coupling was further explored.Meanwhile,the metal diaphragm assembly and the whole coupling were taken as the experimental objects to carry out the comparison of experimental and simulation data.Study results show that the average deviation of the first five-order natural frequencies of the metal diaphragm assembly is within 5%,and the impedance curve of the whole coupling is in good agreement.The average deviation in the frequency band is within 5%,and the frequency deviation corresponding to the peak value of the curve is within 3%;the virtual material method is suitable for the equivalent modeling of the multi-layer bolted joint surface,and each layer of joint surface is equivalent to a layer of virtual material with higher calculation accuracy;the number of di-aphragms mainly affects the first-order natural frequency,and the vibration isolation effect decreases with the increase of the number of diaphragms;the thickness of the diaphragm will affect the position of multi-ple natural frequencies.As the thickness of the diaphragm increases,the natural frequency moves to high frequency,and the vibration isolation effect gradually decreases.