Research colloquium: Lecture on the influence of non-modal damping on forced vibrations of structures

As part of the research colloquium for final theses, doctoral and habiliation candidates, we cordially invite you to join us on Tuesday, April 28, 2026 at 4:30 pm in room 3516 (Mönchebergstr. 7). We are pleased to announce the lecture by Dr.-Ing. Sahar Hetzler, B.Sc., M.Sc. with the title

"Influence of non-modal damping on forced vibrations of structures"

We look forward to seeing you there!

Abstract

In this thesis the influence of non-modal damping on the free and forced vibration behavior of structures is investigated. Since real systems often do not have real eigenvectors, the standard approach to real decoupling is generally no longer applicable. In addition, complex modes lead to phase shifts of the node movements among each other, so that zero crossings and extrema are no longer fixed in space and wandering node lines arise. First, the mathematical basics are prepared and the effect of complex modes on the solution behavior is summarized. Using the example of a damped bending beam, the effects of complex eigenvectors on frequency response and forced oscillations are systematically illustrated. Subsequently, an efficient calculation method for the frequency response matrix is developed and the theoretical findings are validated by numerical simulations and experimental measurements. The results show a very good agreement and illustrate the characteristic occurrence of wandering nodes as an expression of non-modal damping. The work thus contributes to the understanding, modeling and realistic prediction of the dynamic behavior of complex damped structures.