Finite Element Modelling of Engineering Systems

Significant Achievements, Anticipated Outcomes and Future Work

A major research initiative carried out in 2003 was the simulation of forming of lightweight materials for automotive body panels. Finite element simulations were carried out to predict the behaviour of lightweight laminate structures consisting of composite and metals (FML). These material systems offer significant weight savings over conventional metallic structures whilst retaining excellent mechanical properties. Research of this nature is the first of its kind in the world. FML stamp forming and has good potential for the use of these systems in the future generation of cars. Future work will involve developing coupled thermal-structural simulations to develop damage models and establish a framework for manufacturing these systems in a production environment.

Figure1. Simulation of delamination in channel forming of FML systems

Child Restraint Capsules (CRC) are currently used to protect infants while they are travelling in motor vehicles. Whilst the effectiveness of CRC’s in preventing injury and death in frontal collisions has been demonstrated, the performance ofthe CRC’s in side impacts has not been fully assessed. The goal of this project is to evaluate the existing child restraint systems during side impact collisions, and to provide useful information on the possibilities for improved design of child restraint systems. A multi-body dynamics model for the dummy to be used in developing safer CRC has been developed. This model has been validated with experimental results and work is underway to improve the design of the CRC by adding energy absorption materials.

Figure 2. Comparison of experimental and simulated head accelerations

A finite element model of a general honeycomb crash barrier that can be used to investigate the effect of varying dimension and structural properties along with impact conditions on the crushing behaviour under combined axial and shear loading has been developed. The finite element model developed has been validated with experimental data collected by the Department of Transport and Regional Services. In addition to the understanding the mechanics of deformation during impact, this model can provide a means of effectively designing these barriers so that crash barriers provide a reliable way of conducting crash tests.

Computational Techniques Used

The computational techniques that have been used have been based on finite element and finite difference schemes. LS-DYNA and ABAQUS were the major finite element software systems used. Analysis involved solving large (100,000+) nonlinear systems of equations involving material and geometrical nonlinearities with adaptive meshing techniques. Explicit formulations were used in the finite element analysis.

Due to the highly computational nature of simulations (30-50+ hours of CPU time for each run), the supercomputer and software systems at the APAC facility were extremely valuable in obtaining meaningful results for various projects.

Publications, Awards and External Funding

External Funding and Awards

Stamp Forming of lightweight fibre-metal laminate systems. Project ID:LP0347021, 2003-2005, ARC linkage scheme.

Stamp Forming of FML systems: 2002-2004, Ford URP scheme

Publications

[1] G. Brambley, L. Mosse, J. Baird, S. Kalyanasundaram, CFD Analysis of Take-Off Aids in WIG Craft, AIAC 2003, Brisbane, Australia, July 2003.

[2] L. Mosse, G. Brambley, J. Baird, S. Kalyanasundaram, Investigation of Sea Swell Effects on the Performance of WIG Craft, AIAC 2003, Brisbane, Australia, July 2003.

[3] Mosse L., Cantwell W., Cardew-Hall M.J., Compston P., Kalyanasundaram S., “Stamping Analysis of Steel-Composite Laminates”, ICME 2003, Melbourne, Australia, October 2003.

[4] Zhang S., Hodgson P.D., Cardew-Hall M.J., Kalyanasundaram S., “A Finite element simulation of micro-mechanical frictional behaviour in metal forming”, Journal of Materials Processing Technology, 134, pp. 81-91, 2003

[5] Doolan M.C., Kalyanasundaram S., Hodgson P., Cardew-Hall M., “Use of Image Recognition Techniques in the Analysis of Sheet Metal Forming Force Signature Curves”, Journal of Manufacturing Science and Engineering, Transactions of ASME, Vol. 125, pp. 363-368, 2003

[6] Stevanovic D., Kalyanasundaram S., Lowe A., Jar P.Y., “Mode I and Mode II Delamination Properties of Glass/Vinyl-ester Composite Toughened by Particulate Modified Interlayers”, Composites Science and Technology, V 63, N 13, October 2003, pp. 1949-1964.