Cushioning And Mechanical Properties Analysis Of Kelvin Structure

The study of cushion structure plays an important role in the development of the packaging and transportation industry.The honeycomb structure is used mostly in the traditional cushion materials.With the development of social economy and the advancement of science and technology,the requirements for the cushion material structure are also increasing,forcing scientific workers to find cushion materials with better performance.In this thesis,the spatial three-dimensional structure of Kelvin cells is analyzed by the finite element method,compared with the honeycomb structure and the regular hexahedron structure.This thesis mainly does the following work:Firstly,the research status of cushion structure is introduced,and the research results and methods of former researchers are summarized.After studying and analyzing a variety of spatial polyhedrons,the Kelvin structure is defined as the main research object.CAD geometry model is established by three-dimensional mapping software UG.In view of the deficiencies in the current cushion structure research,this thesis decides to use a finite element method to analyze the Kelvin structure.Secondly,the Kelvin structure and the finite element model are established.By comparing and analyzing the spatial structure of Kelvin cell bodies with different cell sizes,it is observed that the Kelvin space structure which is formed under the specific cell unit size has the same deformation,stress distribution,carrying capacity,and energy absorption performance.This provides some references for the design of the cushion structure.For products with equivalent performance,the smaller the size,the greater the difficulty in processing.Selecting a larger size of the cell body and stacking it into a cushion structure will facilitate production.The deformation and stress distribution of the Kelvin structure,the honeycomb and the regular hexahedron structure are compared and analyzed.It is observed that the Kelvin structure deforms layer by layer in the dynamic impact.The cell walls in contact with the rigid masses are initially buckled,and the initial buckling of the honeycomb structure occurs first in the middle cell surface of the honeycomb structure.The buckling form extends from the middle to both sides.The stress concentration is small.The deformation of the regular hexahedral structure is that the structural cell wall firstly creases and then flexes along the initial fold.Finally,by comparing the nominal stress strain curve and the energy absorption performance of the Kelvin structure with the honeycomb and the regular hexahedron structure,two peaks of the Kelvin structure appear which are smaller than the peak stress of the honeycomb structure under the dynamic impact.The stress in the platform stress stage is close to that of the honeycomb structure platform,which is greater than the platform stress of the regular hexahedral structure.By comparing the energy absorption curves,it can be concluded that the standard stress of the Kelvin structure absorbs the normalized energy per unit volume,and the standard stress is small.The total energy absorption is slightly smaller than the honeycomb structure,and is far greater than the regular hexahedral structure.