Research On The Dynamic Model Of Composite Honeycomb Sandwich Structure

In the development of aerospace industry,structural lightweight has always been the focus of attention of researchers.At the same time,as an effective means to improve the viability of aerospace systems,microwave absorption technology is highly valued by all countries in the world.The composite honeycomb sandwich structure is made of the honeycomb sandwich after being immersed by the absorbing glue,which has the double functions of carrying and absorbing wave.It has the advantages of designability,high specific strength,high specific stiffness and so on.It can be widely used in the main and secondary bearing structures of aircraft.The composite honeycomb sandwich structure combines the structure absorption with the coating absorption.The products made of this material will have more excellent absorption performance.In order to explore the static mechanical properties and dynamic response model of composite honeycomb sandwich structure,the research work has been done:This paper first introduces the basic theory of sandwich structure,and analyzes the advantages and disadvantages of each equivalent model in statics calculation and dynamics analysis.The equivalent parameters of hexagonal honeycomb core layer are studied.Taking aluminum honeycomb as an example,the finite element model is established to analyze and compare various equivalent methods.Then,the reduction model in static load and dynamic analysis is compared with the refinement model by using the double scale analysis method.Then,the flat compression,shear and three-point bending tests are carried out on the composite honeycomb sandwich structure,and the material performance parameters of the composite honeycomb sandwich structure are obtained.The material properties of honeycomb paper were obtained by the experiment.According to the obtained mechanical parameters,the equivalent constitutive relation of the composite honeycomb sandwich structure is obtained,and then the dynamic finite element model is established to analyze the composite honeycomb sandwich structure.Finally,through the dynamic test of sandwich panel and sandwich beam,the natural frequency and modal shape of the structure are obtained.The test results are compared with the finite element dynamic model.The results show that the finite element calculation results are close to the actual results.The reliability of the finite element model is confirmed and the method is feasible.