1 |
Numerical Methods for Predicting the Dynamic Crushing Response and Energy Absorption of Composite Aluminum Honeycomb Sandwich StructuresVolk, Cody R 01 June 2020 (has links) (PDF)
Edgewise crushing responses of composite aluminum honeycomb sandwich structures were predicted using finite element analysis (FEA) software LS-DYNA by modeling the honeycomb as a material with anisotropic properties. The goal of the project was to develop a process for modeling the sandwich structure to rapidly iterate possible solutions for a safer workstation train table. Current workstation tables are too rigid and may cause injury or death in a head-on collision. Experimental compression tests were used to calibrate the aluminum honeycomb core with material type 26 (MAT 26, honeycomb). A published composite tensile test was used to validate the use of material type 22 (MAT 22, composite damage) for laminates. Finally, a model was made to recreate the results of a published compression test of an aluminum honeycomb sandwich structure with aluminum sheet metal face sheets to confirm contact types.
With each component of the model verified separately, three plain weave composite aluminum honeycomb sandwich structures were modeled, one with [0/90] composite sheets completely bonded to the core, one with [0/90] composite sheets partially bonded to the core, and one with [±45] composite sheets partially bonded to the core. The failure modes for each sandwich structure were previously shown through research and the elastic region of the response was checked for accuracy using a simple beam theory. The analysis suggests that incorporating unbonded zones into the sandwich structure will change the failure mode from general buckling to face wrinkling, which effectively lowers the failure strength while not sacrificing energy absorption throughout loading. The analysis also indicates that using an angled ply orientation will lower the initial stiffness and the failure load. Future work is recommended such as performing compression tests with composite aluminum honeycomb sandwich structures and integrating delamination failure modes into the model using cohesive elements.
|
2 |
Structural Analysis and Finite Element Modeling of Aluminum Honeycomb Sandwich StructuresDoukoure, Maimouna 05 1900 (has links)
The objective of this research is to determine how the sandwich's physical characteristics have an impact on the mechanical properties, determine under what conditions the specimens will be lighter and mechanically stronger, and determine if the use of an aluminum honeycomb sandwich as a construction material is feasible. The research has aimed at the use of aluminum sandwiches as light and strong material. The study of the structural layers' damage resistance and tolerance demonstrated that the top and bottom layers play a crucial role. The thesis presents three test results from aluminum honeycomb sandwich compression horizontal, compressive vertical, and bending tests. Also, each group was displayed mechanically and simulated in Abaqus. The study determines the mechanical properties such as maximum elastic stress-strain, ultimate stress-strain, fracture point, density, poison ration, young modulus, and maximum deflection was determined. The energy absorbed by the FEA, such modulus of elasticity, resilience, and toughness, the crack propagation, the test's view shows aluminum honeycomb behaved like a brittle material with both compression test. And the maximum deflection, crack propagation, shear forces, bending moment, and images illustrated that the layers play a crucial role in the 3-point bend test.
|
Page generated in 0.0651 seconds