Hostname: page-component-76fb5796d-22dnz Total loading time: 0 Render date: 2024-04-26T07:54:04.067Z Has data issue: false hasContentIssue false

Optimization of Sandwich Monocoque Car Body with Equivalent Shell Element

Published online by Cambridge University Press:  05 May 2011

C.-K. Chang*
Affiliation:
Department of Mechanical Engineering, National Taiwan University, Taipei, Taiwan 10617, R.O.C.
J.-H. Cheng*
Affiliation:
Department of Mechanical Engineering, National Taiwan University, Taipei, Taiwan 10617, R.O.C.
*
*Graduate student
**Professor, corresponding author
Get access

Abstract

This research proposes a straightforward and efficient method to optimize a sandwich monocoque car body with the developed equivalent shell element based on stiffness equivalence. The fact that stiffness rather than strength is dominant constraint for ordinary car body optimization is demonstrated. A simple but heavy flat chassis plate is utilized as upper bound, while an ideal monocoque is used as lower bound for an actual car body optimization. Convergence hours can be significantly reduced with the equivalent element and the initial-bounded method. A novel electric car body optimization is presented, fulfilling UltraLight Steel Auto Body (ULSAB) stiffness requirements and showing similar optimal weight results as a conventional approach with a much lower analysis time cost.

Type
Articles
Copyright
Copyright © The Society of Theoretical and Applied Mechanics, R.O.C. 2007

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

1.Kuenzi, E. W., Minimum Weight Structural Sandwich, USDA Forest Service Research Note FPL-086, Forest Products Laboratory, Madison, USA (1965).Google Scholar
2.Gibson, L. J., “Optimization of Stiffness in Sandwich Beams with Rigid Foam Cores,” Materials Science and Engineering, 67, pp. 125135 (1984).CrossRefGoogle Scholar
3.Demsetz, L. A. and Gibson, L. J., “Minimum Weight Design for Stiffness in Sandwich Plates with Rigid Foam Cores,” Materials Science and Engineering, 85, pp. 3342 (1987).CrossRefGoogle Scholar
4.Theulen, J. C. M. and Peijs, A. A. J. M., “Tech. Note: Optimization of The Bending Stiffness and Strength of Composite Sandwich Panels,” Composite Structures, 17, pp. 8792 (1991).CrossRefGoogle Scholar
5.Vinson, J. R., The Behavior of Sandwich Structures of Isotropic and Composite Materials, 1st Edition, Technomic Pub. Co., Lancaster, Pa., USA, pp. 271303 (1999).Google Scholar
6.Ashby, M. F., et al., Metal Foams: A Design Guide, 1st Edition, Butterworth-Heinemann, Woburn, MA, USA, pp. 113149(2000).Google Scholar
7.Triantafillou, T. C. and Gibson, L. J., “Failure Mode Maps for Foam Core Sandwich Beams,” Materials Science and Engineering, 95, pp. 3753 (1987).CrossRefGoogle Scholar
8.Petras, A. and Sutcliffe, M. P. F., “Failure Mode Maps for Honeycomb Sandwich Panels,” Composite Structures, 44, pp. 237252 (1999).CrossRefGoogle Scholar
9.Alspaugh, D. W. and Huang, S. N., “Minimum Weight Design of Axisymmetric Sandwich Plates,” AIAA J., 18, pp. 16831689 (1976).CrossRefGoogle Scholar
10.Ringertz, U., et al., “Computer Sizing of Sandwich Constructions,” Composite Structures, 5, pp. 251279 (1986).CrossRefGoogle Scholar
11.Ermolaeva, , et al., “Materials Selection for An Automotive Structure by Integrating Structural Optimization with Environmental Impact Assessment,” Materials and Design, 25, pp. 689698 (2004).CrossRefGoogle Scholar
12.Zenkert, D., The Handbook of Sandwich Construction, 1st Edition, EMAS, Cradley Heath, UK, pp. 129146 (1997).Google Scholar
13. UltraLight Steel Auto Body Engineering Report: Testing and Results, PORSCHE Engineering Services, Inc. (1995).Google Scholar
14.Hu, S. Y. and Cheng, J. H., “Development of an Object-oriented Optimization Software for Industrial Utilization,” Proceedings of the 4th Conference of OPTDES, Japan (2004).Google Scholar
15.Hu, S. Y. and Cheng, J. H., “Development of the Unlocking Mechanisms for the Complex Method,” Computers and Structures, pp. 19912002 (2005).CrossRefGoogle Scholar
16.Allen, H. G., Analysis and Design of Structural Sandwich Panels, 1st Edition, Pergamon Press, Oxford, UK (1969).Google Scholar
17.Divinycell® Hgrade, DIAB Co., Laholm, Sweden.Google Scholar
18.Niu, M. C.-Y., Composite Airframe Structures: Practical Design Information and Data, 1st Edition, Technical Book Company, Los Angeles, pp. 41111 (1992).Google Scholar
19.Lock, R. H., “1993 New Car Data,” Journal of Statistics Education, 1 (1993).Google Scholar
20.Roark, R. J. and Young, W. C., Formulas for Stress and Strain, 5th Edition, McGraw-Hill, New York, pp. 89208 (1975).Google Scholar
21.Wang, A. J. and McDowell, D. L., “Optimization of a Metal Honeycomb Sandwich Beam-Bar Subjected to Torsion and Bending,” International Journal of Solids and Structures, 40, pp. 20852099 (2003).CrossRefGoogle Scholar
22.Cheng, S., “Elasticity Solution of Torsion of Sandwich Plates,” Journal of the Engineering Mechanics Division, 94(EM2), pp. 605620 (1968).CrossRefGoogle Scholar
23.Megson, T. H. G., Aircraft Structures for Engineering Students, Edward Arnold, London, UK (1972).Google Scholar