Research On Vibration Reduction And Noise Reduction Of Gearbox Based On Phononic Crystals

In production and life,with the widely used applications of reducer and accelerator in automobile,aerospace,aviation and other industrial fields,the noise pollution of gearbox is becoming more and more serious.Phononic crystals and periodic structures have band gap characteristics.When the elastic wave is in a specific range,its propagation is suppressed in the structure,which provides a new idea for controlling the structural vibration of gearbox and solving the noise pollution.In this paper,the band gap theory and finite element method are used to analyze the band gap characteristics and propagation rules of vibration waves in periodic support shaft and phononic crystal plate,and the feasibility of two kinds of design ideas in vibration and noise suppression of gearbox system is investigated.The main research contents include:1.Starting from the bending vibration equation of Timoshenko beam,the transfer matrix method is applied to get the propagation characteristics of elastic wave in the shaft.On this basis,the rotation factors of the shaft system are further considered,and two kinds of periodical support drive shafts are constructed.By means of numerical calculation and simulation analysis,the regulation of the structural parameters and material parameters to the band gap is studied by a specific example.2.The structure of the phononic crystal plate is studied by the finite element method,and the influence of different structural parameters on the band gap width and vibration attenuation is investigated.Further study of the common L plate in structural engineering,mainly for its large band noise radiation,the damping mechanism of phononic crystal is introduced,according to the influence rule of band gap parameters,the design parameters of local oscillator are studied and analyzed,and the vibration suppression of L plate is realized,and the optimization of the main parameters of the oscillator is also studied.3.The two design ideas of the periodic support shaft and the phonon crystal board are introduced into the vibration and noise reduction of the gear box system,and the feasibility of the application is analyzed.In view of the main damping frequency demand of the gear box,the location of the local oscillator is determined and the matching of the vibrator parameters is completed.Finally,the vibration test platform of the gear box was built,and the vibration signals of the two gear cases were measured,and the experimental verification was completedResearch shows that the periodic support shafting vibration suppression performance influenced by support,periodic support design of gearbox shafting structure on the vibration suppression performance improvement is not obvious;The vibration and noise in the frequency band can be reduced by using the vibration damping mechanism of the phononic crystal in the L type plate structure.The phononic crystal damping mechanism applied to gear box design through reasonable design,laying position of local oscillator and oscillator parameters matching,can realize the specified frequency band vibration and noise suppression effect.These studies are of great significance to expand the theory and application of phononic crystal vibration and to suppress the vibration and noise of the gear box.