Using SEMM to Identify the Joint Dynamics in Multiple Degrees of Freedom Without Measuring Interfaces
As the number of models created in a modular fashion increase, the need for accurate identification of real joint dynamics rises. Since joint dynamics are a consequence of component-to-component interaction, they are only present in the assembled state. Yet, it is in the assembled state that measuring the interface degrees of freedom is practically infeasible. Nevertheless, the effects of the joint are present in measurements throughout the component, i.e. the joint dynamics are observable. In this work, system equivalent model mixing is used to expand an experimental measurement with interface degrees of freedom—either rotational or translational—extracted from a numerical model. Subsequently, joint dynamics can be obtained by applying classic frequency based decoupling methods. The strength of this method lies in the ability to test different interface configurations from a single measurement campaign, limited only by the actual number of sensor or impact locations. The paper shows that an updating scheme can be used to identify joint dynamics without directly measuring interfaces.
KeywordsSystem equivalent model mixing Interfaces Joint identification Optimization
The project has received funding from the European Union’s Horizon 2020 research and innovation programme under the Marie Sklodowska-Curie grant agreement No. 721865.
- 1.Ewins, D.J., Nowell, D., Petrov, E.: The importance of joints on the dynamics of gas turbine structures. In: Segalman, D.J., Bergman, L.A., Ewins, D.J. (eds.) Report on the SNL/NSF International Workshop on Joint Mechanics, Arlington, Virginia, pp. 23–32, Sandia National Laboratories, Albuquerque (2006)Google Scholar
- 5.de Klerk, D., Rixen, D.J., de Jong, J.: The frequency based substructuring (FBS) method reformulated according to the dual domain decomposition method. In: IMAC-XXIV A Conference & Exposition on Structural Dynamics (2006)Google Scholar
- 6.Voormeeren, S.N., van der Valk, P.L.C., Rixen, D.J.: Practical aspects of dynamic substructuring in wind turbine engineering. In: Structural Dynamics and Renewable Energy, Vol. 1. IMAC-XXVIII A Conference & Exposition on Structural Dynamics, July 2011. Springer, New York/Jacksonville, FL (2010)Google Scholar
- 7.Meggitt, J.W.R., Moorhouse, A.T.: The in-situ decoupling of resiliently coupled sub-structures. In: 24th International Congress on Sound and Vibration, July, London, pp. 1–8 (2017)Google Scholar
- 8.Haeussler, M., Klaassen, S.W.B., Rixen, D.J.: Comparison of Substructuring based techniques for dynamic property identification of rubber isolators. In: ISMA 2018 - International Conference on Noise and Vibration Engineering, Leuven, p. 1 (2018)Google Scholar