A MAC based excitation frequency increasing method for structural topology optimization under harmonic excitations

Abstract

-This work is focused on the topology optimization of structures that are subjected to harmonic force excitation with prescribed frequency and amplitude. As an important objective of such a design problem, the natural resonance frequency of the structure is driven far away from the prescribed excitation frequency for the purpose of avoiding resonance and reducing the vibration level. Therefore when the excitation frequency is higher than the natural resonance frequency of the structure, the natural resonance frequency will decrease, then the optimum topology configuration will be distorted with large amount of gray elements. A MAC (Modal Assurance Criteria) based excitation frequency increasing method is proposed to obtain a desired configuration. MAC is adopted here to track the natural resonance frequency which can provide the baseline reference for the current excitation frequency during the optimum iterative procedure. Then the excitation frequency increases progressively up to its originally prescribed value. By means of numerical examples, the proposed formulation can generate effective topology configurations which can avoid resonance.

A moving morphable component‐based topology optimization approach considering transient structural dynamic responses

“…In addition, Figure 24 plots the time evolution of the fundamental natural frequency of some intermediate structures obtained at different optimization steps. These results seem to be consistent with other research on time‐invariant problems which found that the optimized structures tend to shift the fundamental natural frequency away from the excitation frequency 13,50 …”

Finite element modeling and random vibration analysis of BGA electronic package soldered using lead free solder alloy − Sn-1Cu-1Ni-1Ag

“…In another study, the dynamic behavior of the fixtured workpiece subjected to time-and space-varying machining loads is simulated using a forced vibration model [12]. Topology optimization of structures with damping that is exposed to harmonic force excitation with prearranged frequency higher than its natural resonance frequency is done in another study [13].…”