Progressive Damage Simulation And Strength Prediction Of Foam-core Sandwich Structure With Antennas

With the development of aerospace industry, to achieve integration of aircraft structure, theconcept of conformal bearing antennas gradually formed to compromise effective load, availablespace and aerodynamic performance of an aircraft. The application of conformal bearing antenna isextremely attractive in the fields of aerospace and guidance because of its low occupation of extraspace and small influence on flight attitude, and the research of which shows great engineering valuesand significances of national defense.In this essay, firstly, in-plane compressive and out-of-plane tensile experiments of the foam-coresandwich structure with and without antennas were carried out. Test data were then analyzed to studythe influences of antenna on the mechanical properties and structural weight, which laid essentialbasis for the strength analysis and potential application of formal bearing antennas.Secondly, a new3D finite element model was established in the framework of ABAQUSsoftware to analyze the strength of foam sandwich structure by introducing three-parametergeneralized failure criterion and Tsai-Wu failure criterion for the purpose of simulating theprogressive damage of foam-core sandwich structure and composite laminates. By using this model,in-plane compression and out-of-plane tension of the foam-core sandwich structure were simulated,and its structural mechanical behaviors under in-plane compressive and out-of-plane tensile loadingswere also predicted. Furthermore, effects of the thickness and ply angle of composite laminates andthe thickness of foam-core on structural strength were discussed. In the paper, an antenna arraystrength forecasting model was established based on ABAQUS software to simulate the effects ofdifferent antenna arrays on the structure.Regarding the complex stress state applied on general foam core conformal antenna structures, astrength prediction model considering various biaxial loadings was presented using UMAT substratein ABAQUS software. The model was then adopted to simulate the biaxial tension, biaxialcompression, biaxial tension-compression and biaxial compression-tension of foam core sandwichstructure.