Analysis Of Impact Resistance Of Cavity-filled Composite Multi-cell Structure

The multi-cell structure has excellent mechanical properties with light weight,high shear resistance and deformability,and the internal periodic cell has the characteristics of wave pattern transformation and impedance mismatch.It has been widely used in the field of underwater target of anti-detection stealth and anti-shock.The locally resonant unit composed of metal element coated with rubber matrix exhibits the band gap in specific low frequency in sound absorption.But there are less studies on the mechanical properties of the structures.Based on this,a new type of composite multicellular structure filled with core in annular cavity of chiral system structure is proposed.Then research on the in-plane impact mechanical properties and underwater impact properties are carried out.The main study process is as follows:(1)The composite chiral and anti-chiral multi-cell structures of the annular cavity filled core were designed.The constitutive equation of non-linear materials in the calculation of display dynamics is fitted.(2)The ABAQUS/Explicit is used to establish the calculation model of in-plane impact in composite multi-cell structure.The research is carried out under different impact velocity.And it analyzed the dynamic properties of the structure and the deformation mode.The research also analyzed the dissipation of stress waves in the structure and the process of transformation of the form of wave,and the energy absorption mechanism and dynamic characteristics of the structure are analyzed.In-plane mechanical properties of different types of composite structures and cavity structures were compared,including bearing capacity,reaction force and energy absorption.(3)Using the method of acoustic-structure interaction,the shock response and antishock mechanism of the composite multi-cell structure under the action of plane shock wave of underwater explosions are operated.The fluid-structure interaction mechanism and the time history of incident pressure are analyzed.The study also analyzed the transient response,the distribution characteristics of stress transmission and the process of energy dissipation in structure.The impact response and underwater impact resistance of cavity and composite structure under underwater impact are compared and analyzed,and the research reveals the influence of core filling on the structural compressive stability and the distribution of impact stress.(4)This study compares the impact properties of dynamic response,energy dissipation and response of reaction of supports under different shock pressures with composite chiral structure and reversed chiral structure.And it analyzed the differences between the process of waveform conversion and the overall deformation mechanism of the structure.The research discussed the effects of structural parameters(including structural height and distribution form of core)on the shock performance of composite reversed chiral structure,which can provide reference for distribution of energy dissipation and functional design of impact structures.