Analysis Of Energy Absorption Characteristics Of Corrugated Sandwich Cylindrical Shells Under Axial Load

Corrugated sandwich cylindrical shell structure has a wide application prospect in the fields of architecture,aerospace,transportation and other fields because of its high bearing capacity,high specific stiffness and specific strength,as well as good energy absorption performance,heat transfer performance,damping and damping performance.At present,the research on the corrugated sandwich cylindrical shell structure mainly focuses on the quasi-static mechanical properties of the basic configuration.The understanding of its dynamic wave characteristics and related failure mechanisms is not perfect,and there is also a lack of more configuration innovation.In this paper,the mechanical properties of the corrugated sandwich cylindrical shell structure under axial load are studied by means of experiments,theory,numerical simulation and other methods.The main work is as follows:First,four kinds of corrugated sandwich cylindrical shell structures including longitudinal corrugated core,longitudinal staggered corrugated core,circumferential corrugated core and circumferential staggered corrugated core are designed.Poly(lactic acid)(PLA)was used to prepare it by additive manufacturing method,and its bearing capacity,deformation process and failure mode were studied by axial compression test method,and a prediction formula of structural bearing capacity considering multiple failure modes was established.At the same time,numerical simulation of the axial compression process of the corrugated sandwich cylindrical shell structure was conducted using the finite element software ABAQUS,which confirmed the correctness and effectiveness of the finite element settings.Second,based on the FEM software ABAQUS,the finite element model of metal corrugated sandwich cylindrical shell structure is established,and the axial compression deformation process of four structures is simulated.The research shows that the longitudinal corrugated sandwich cylindrical shell structure is significantly higher than the circumferential corrugated sandwich cylindrical shell structure in terms of load carrying capacity and energy absorption performance under quasi-static axial compression loading,and the staggered corrugated core design also significantly improves the load carrying capacity and energy absorption efficiency of the structure.In addition,numerical simulations were conducted on the axial impact process of longitudinal corrugated core and staggered corrugated core sandwich cylindrical shell structures at different speeds.It was found that the interaction between the core material and the skin improved the bearing capacity and energy absorption performance of the structure,achieving a "1+1>2" effect.Comparing the specific energy absorption of the two structures under different impact speeds,it is found that the staggered corrugated core design structure has better energy absorption performance under axial impact.The effects of the thickness of inner and outer skin and the number of corrugated cells on the deformation mode and energy absorption performance of longitudinally corrugated sandwich cylindrical shells under axial impact were studied.The results show that the deformation of the longitudinal corrugated core layer is synchronized with the weak side of the inner and outer skin strength,and the change of the inner and outer skin thickness will change the deformation mode of the corrugated sandwich cylindrical shell structure.At the same time,the thickness of the inner and outer skin,the number of corrugated cells and the impact speed will have a certain impact on the energy absorption performance of the structure.With the increase of impact velocity,the initial peak force,specific energy absorption,and average compressive force of the structure increase.When the inner skin of the two structures is too thick or the outer skin is too thick,the effective deformation distance of the structure will be reduced,which is not conducive to the energy absorption performance of the structure.When the corrugated cell number is 12,the compression deformation of the structure shows the most stable axisymmetric deformation mode,which is more suitable for the design of energy-absorbing components.Finally,the axial impact of circular corrugated core and staggered corrugated core sandwich cylindrical shell structure at different speeds is numerically simulated.It is found that similar to the longitudinal corrugated sandwich cylindrical shell structure,the interaction between skin and core material and the design of staggered corrugated core are also conducive to the improvement of load-bearing capacity and energy absorption performance of circular corrugated sandwich cylindrical shell structure.The effects of the thickness of the inner and outer skin and the number of corrugated cells on the deformation mode and energy absorption performance of a circular corrugated sandwich cylindrical shell under axial impact were studied.The results show that the overall deformation mode of the structure is dominated by the corrugated core layer,which is not affected by the thickness of the inner and outer skin.The increase of the thickness of the inner and outer skin and the number of corrugated cells will improve the energy absorption performance of the structure.With the increase of impact velocity,the specific energy absorption and average compression force of the structure increase.In addition,the longitudinal and circumferential corrugated sandwich cylindrical shell structures are compared.It is found that the longitudinal corrugated sandwich cylindrical shell structure has higher energy absorption performance under axial impact,and the longitudinal staggered corrugated core sandwich cylindrical shell structure has the best energy absorption performance,which is most suitable for energy absorption components.