https://paginas.fe.up.pt/~iccs16/CD/721-760/735Belingardi_Boria_Obradovic.pdf

Lightweight design and crash analysis of composite frontal impact energy absorbing structures

Impact resistance and damage tolerance of fiber reinforced composites: A review

Experimental study on crashworthiness of empty/aluminum foam/honeycomb-filled CFRP tubes

Lightweight design of carbon twill weave fabric composite body structure for electric vehicle

Design optimization and manufacture of hybrid glass/carbon fiber reinforced composite bumper beam for automobile vehicle

Natural fiber composites have the potential to be widely applied as an alternative to or in combination with glass fiber composites in sustainable energy-absorbing structures. This study investigat...

Analytical modeling and experimental validation of the low-velocity impact response of hemp and hemp/glass thermoset composites:

Temperature effect on impact response of flax/epoxy laminates: Analytical, numerical and experimental results

The behaviour of composites materials, made of synthetic fibres embedded in a thermoplastic resin, subjected to low velocity impacts, was largely studied in the past. However, in the last years, th...

/pdf/energy-absorption-capability-of-laminated-plates-made-of-4ryrp1yt80.pdf

Energy absorption capability of laminated plates made of fully thermoplastic composite

The design of composite materials seems more challenging compared with that of their metallic counterparts because of their microstructural heterogeneity and sophisticated behavior. The ever-wider use of composite materials for structural applications in the automotive industry makes it necessary to predict their behavior under varying load conditions. This chapter is focused on the experimental and numerical crashworthiness design of carbon fiber-reinforced plastic structures under quasi-static and dynamic axial loading. The material used for this research is a prepreg obtained from high-strength carbon fibers embedded in an epoxy resin. Initially, simple geometries were taken into account to evaluate the influence of several geometric parameters and loading conditions on the final deformation. Afterward, a more complex geometry, equal to that adopted for the frontal impact attenuator of a Formula SAE car, was investigated. For each analysis, the numerical results were compared with those obtained from real axial crushing tests. The study indicates that the deformation behavior of the laminate calculated by using numerical models was in good agreement with experimental results; despite the simplification adopted, the finite element models were able to capture the main crushing parameters with maximum relative errors of 10%.

Lightweight design and crash analysis of composites

This work presents a hybrid optimization approach that couples Efficient Global Optimization (EGO) and Covariance Matrix Adaptation Evolution Strategy (CMA-ES) in the Topology Optimization (TO) of mechanical structures. Both of these methods are regarded as good optimization strategies for continuous global optimization of expensive and multimodal problems, e.g. associated with vehicle crashworthiness. CMA-ES is flexible and robust to changing circumstances. Moreover, by taking advantage of a low-dimensional parametrization introduced by the Evolutionary Level Set Method (EA-LSM) for structural Topology Optimization, such Evolution Strategy allows for dealing with costly problems even more efficiently. However, it is characterized by high computational costs, which can be mitigated by using the EGO algorithm at the early stages of the optimization process. By means of surrogate models, EGO allows for the construction of cheap-to-evaluate approximations of the objective functions, leading to an initial fast convergence towards the optimum in opposition to a poor exploitive behavior. The approach presented here – the Hybrid Kriging-assisted Level Set Method (HKG-LSM) – first uses the Kriging-based method for Level Set Topology Optimization (KG-LSM) to converge fast at the beginning of the optimization process and explore the design space to find promising regions. Afterwards, the algorithm switches to the EA-LSM using CMA-ES, whose parameters are initialized based on the previous model. A static benchmark test case is used to assess the proposed methodology in terms of convergence speed. The obtained results show that the HKG-LSM represents a valuable option for speeding up the optimization process in real-world applications with limited computational resources. As such, the proposed methodology exhibits a much more general potential, e.g. when dealing with high-fidelity crash simulations.

Simonetta Boria

Papers

Analytical modeling and experimental validation of the low-velocity impact response of hemp and hemp/glass thermoset composites:

Temperature effect on impact response of flax/epoxy laminates: Analytical, numerical and experimental results

Energy absorption capability of laminated plates made of fully thermoplastic composite

Lightweight design and crash analysis of composites

Hybrid Kriging-assisted Level Set Method for Structural Topology Optimization.