Study On Load-reducing Plan For Cover System Of A Device Based On Foamed-aluminum Absorption Layer And Optimization Of Its Parameters

The cover system of launching unit of a product bear the transient impact action bycomplex multiphase flow during the course of working, resulting in the failure of delayedfracture of connecting bolts of bearing base on its structure, which will introduce somepotential safety hazards into the normal operation of the product. For this reason, it isimperative to use the buffer absorbing device to load shedding，and it is significant andvaluable to study and solve this physical problem of engineering.As a metal material foamed-aluminium is widely used with its good absorbtioneffective, this paper points out that the plan of buffering energy-absorbing structure ofattached foamed-aluminium absorption layer is adopted to investigate the load sheddingeffect on the cover system. Firstly, it represents the excellent characteristics shown by thefoamed-aluminum absorption layer being energy-absorbing structure, and thesecharacteristics can be subjects investigated to establish a finite element model with unit-cellfoamed aluminum for analyzing its relative performance, from which the stress-straincharacteristic curve of foam aluminum with differently relative density can be obtained,when impacted by impulse loads and the reliability of analyses certified; and then thegeometrical model of cover system is established and the finite element model of coversystem applied in this paper is finally determined by the finite element model based on thecomparison of two classification methods, and the checking can be carried out via the finiteelement model based on two methods and the checking results demonstrate that the finiteelement model of cover system established is reasonable and feasible;The finite elementmodel of cover system in the attached foamed-aluminum absorption layer is establishedand the relative density and thickness of foamed-aluminum materials with different rangesis selected as parameters, in order to investigate the buffering load shedding effect on coversystem at operating, and the aim of buffering load shedding is achieved finally and theselection range of optimal parameters of foamed-aluminum absorption layer.Another structure widely used in buffering energy-absorbing device is described andanalyzed, i.e. thin-walled tube type energy-absorbing structure. The focus for analysis is onthe energy absorption capacity of tubular energy absorption structure with circular crosssection and regular hexagon cross section and the energy absorption capacity of thestructure of circular tube type is superior to that of the structure of regular hexagon tubetype. Taking the circular cross section as research object, its size parameters are optimized on the energy absorption capacity and the size parameters which are finally optimized areobtained. At last, the optimized structure of circular cross section tube type is taken as abuffering energy absorption structure to inspect the load shedding effect on the coversystem, and the results show that taking this structure as the energy absorption device canplay a role in shedding loads. Ultimately, compared with the load shedding effect offoamed-aluminum absorption layer, this effect is better than that of the structure withcircular cross section tube type.