On Selective Mass Scaling for Solid-Shell Elements

The critical time step size in explicit transient analyses depends on the highest discrete frequency, which is, for discretizations composed of thin solid or solid-shell elements, typically related to thickness stretch modes [1]. Selective mass scaling (SMS) methods aim at reducing the number of required time steps by scaling down the highest frequencies. Additionally, SMS methods are designed for preserving accuracy in the lower part of the frequency spectrum. But the use of SMS typically comes at the cost of non-diagonal mass matrices and the need for using iterative solvers in each time step. Therefore, the overall efficiency of SMS depends on the number of time steps, the numerical cost per time step, and the desired level of accuracy. In this contribution, we present first results on the extension of our recent SMS method [2] to solid-shell elements and geometrical non-linearity. We compare our method with SMS concepts from literature with respect to the accuracy in spectral problems and the overall efficiency in transient analyses. REFERENCES [1] G. Cocchetti, M. Pagani and U. Perego. Selective mass scaling and critical time-step estimate for explicit dynamics analyses with solid-shell elements. Computers & Structures, Vol. 127, pp. 39–52, 2013. [2] M. Hoffmann, A. Tkachuk, M. Bischoff and B. Oesterle. Finite element technology-based selective mass scaling for explicit dynamic analyses of thin-walled structures using solid elements. COMPDYN 2023, 9th ECCOMAS Thematic Conference, M. Papadrakakis, M. Fragiadakis (eds.), Athens, Greece , pp. 1974–1982, 2023.