This content is not included in your SAE MOBILUS subscription, or you are not logged in.
Fatigue Life Calculation of an Automotive Shock Absorber Shim Assembly Using Different Simulation Techniques
ISSN: 0148-7191, e-ISSN: 2688-3627
Published April 08, 2013 by SAE International in United States
Annotation ability available
In an automotive twin tube shock absorber, thin structures used in piston and base valve sub-assembly are called shims. These shims are used in proper combination to achieve particular damping force characteristics and these shims will be operating continuously throughout the life of shock absorber. Any failure of shims during lab/ vehicle testing will increase the development time and cost considerably. Hence, predicting the operating life of shim assembly is very important during shock absorber development stage.
In order to predict the life of the shim assembly, simulation techniques can be applied with fair degree of accuracy. Currently, during structural simulation of shim assembly, it is assumed that fluid pressure is acting uniformly over the entire shim to find stress intensity. This approximation is taken into account to predict the fatigue life of shim assembly.
This paper proposes additional technique to carry out close to real life shim simulation. In this proposed technique, fluid structure interaction (FSI) is considered for modelling the shock absorber fluid flow and piston shim assembly. In this simulation, actual pressure developed during shock absorber travel will be acting on shim assembly. The fatigue life is calculated for current and proposed techniques. These results are compared with experimental results for deciding appropriate simulation technique.
CitationKulkarni, S., Magdum, M., and B, R., "Fatigue Life Calculation of an Automotive Shock Absorber Shim Assembly Using Different Simulation Techniques," SAE Technical Paper 2013-01-1240, 2013, https://doi.org/10.4271/2013-01-1240.
- Dixon , J.C. Shock Absorber Handbook Second SAE International Warrendale, PA 978-0-7680-1843-1 2007
- Herr , F. , Mallin , T. , Lane , J. , and Roth , S. A Shock Absorber Model Using CFD Analysis and Easy5 SAE Technical Paper 1999-01-1322 1999 10.4271/1999-01-1322
- Collins , J. and Cwycyshyn , W. Tuning Guide for Deflected-Disc Suspension Dampers SAE Technical Paper 2006-01-1380 2006 10.4271/2006-01-1380
- Rao , M. , Gruenberg , S. , and Torab , H. Measurement of Dynamic Properties of Automotive Shock Absorbers for NVH SAE Technical Paper 1999-01-1840 1999 10.4271/1999-01-1840
- Kulkarni Swapnil S , Ravi B , Magdum Muragendra A coupled fluid structure interaction simulation of automotive shock absorber using Radioss block explicit solver Hyperworks technology conference 2012