Research On Aluminum Honeycomb FEM Model And Its Application In Simulation Of Car Crash Barrier

Aluminum honeycomb is widely used in various engineering fields because of its high strength, high energy absorption capability and low density. In vehicle occupant safety field, aluminum honeycomb is used to build car crash deformable barriers. The honeycomb fabrication process by the expansion method begins with the stacking of sheets of the substrate material on which adhesive node lines have been printed, then the stacking of sheets can be expanded to form honeycomb cell wall structure. Aluminum honeycomb is highly anisotropic resulting from its fabrication process and has complex deformation properties.This thesis describes a new finite element modeling method of aluminum honeycomb by using shell elements. A computer-based model of honeycomb is developed; the model is built with shell elements and has cell wall structure. Honeycomb out-plane, in-plane and shearing tests are simulated. Simulation of force and honeycomb deformation mode show excellent correlation with experiment data. In order to control the total element number to make the shell honeycomb model applicable in engineering, the cell structure is scaled, and compressive strength is kept by scaling the thickness of shell elements. A scaled shell honeycomb model is built and its deformation mode is optimized. Scaled shell honeycomb model is tested in several load cases and results show the scaled model has similar dynamic and deformation as the real model.Car crash simulation is widely used to control development cost and shorten development period, simulation reliability and accuracy become very important in engineering. Simulation reliability and accuracy depend on algorithms of finite element software and methods of numerical modeling. In car crash simulation, the accuracy of barrier modeling is very important to car crash simulation. Based on scaled shell honeycomb model, PDB (Progressive Deformable Barrier) and ODB (Offset Deformable Barrier) FE model were built, and various load cases were performed. The result of crash simulations with a shell honeycomb model shows excellent correlation with test results.