Research On Anti-explosion And Impact Resistance Of Sandwich Structure For Aviation

With the rapid development of aviation and aerospace,the protection of the outer casing and important internal instruments becomes more and more important.With the development of science and technology and industrial production,the separation design of structure and function can no longer meet the needs of people for the application of protective structures.Therefore,researchers and designers have a great interest in new advanced structures that combine excellent mechanical properties with multiple properties.Based on the design characteristics of corrugated sandwich structure and pyramid lattice sandwich structure,this paper proposes a sinusoidal beam sandwich structure with different amplitude-period ratio,curved beam cross-sectional area and cross-section adjacent side length ratio.Three variables were used to analyze the quasi-static compression performance,impact resistance and air-explosion resistance of different variable structures by numerical simulation.Mainly divided into the following sections:1.The three-dimensional modeling of the sinusoidal beam sandwich structure is briefly introduced,and the relative density calculation formula is derived based on the theory of mechanical characterization of the sandwich structure.Using Abaqus/Standard for quasi-static compression numerical simulation,the deformation process and failure modes of the sinusoidal beam sandwich structure under quasi-static compression are mainly presented as the bending of the two beams and the plastic hinge expansion at the peaks and valleys.The influence of the cross-sectional area and the length of the adjacent side of the curved beam on the anti-pressure performance is greater than that of the curved beam amplitude-period ratio.2.Using Abaqus/Explicit to simulate the SHPB impact test of the sinusoidal beam sandwich structure,it is concluded that the impact resistance of the sinusoidal beam sandwich structure is approximately irrelevant to the strain rate,and the amount between the transmitted wave and the incident wave occurs.The reduction in grades reflects excellent impact and flameproof properties and good energy absorption characteristics.3.The Conwep algorithm in Abaqus/Explicit is used to simulate the air-explosion experiment of the sinusoidal beam sandwich structure.It is concluded that the larger the amplitude-period ratio,the stronger the anti-explosion performance of the sandwich structure and the larger the cross-sectional area of the curved beam,the anti-impact performance will be better.Moreover,when the explosion distance increment is constant,the amount of deformation of the core becomes larger,indicating that the explosion distance has a great influence on the antiknock performance of the sandwich structure.As the amount of explosive increases,the center deflection of the rear panel increases,and the amount of core deformation increases.4.Compared with the pyramid lattice structure,it is found that the quasi-static compressive performance of the sinusoidal beam sandwich structure is 70%higher than that of the pyramid lattice sandwich structure,and the dynamic compressive strength under the impact load is higher than that of the pyramid lattice clamp.The core structure has increased by 54%.Under the same static compressive strength,the dynamic compressive strength of the sinusoidal beam sandwich structure is smaller than that of the pyramid structure,which has better deformation energy absorption effect and can effectively block the conduction of the load from the forward wave to the back wave surface.5.From the three numerical simulations of quasi-static compression,SHPB impact and air explosion shock,combined with the consideration of practical engineering applications,it can be concluded that the amplitude-period ratio is 0.8,the square section,and the cross-sectional area is 1.35mm×1.35mm.It has excellent compression resistance and anti-explosion and impact resistance while taking into consideration the stability.