Targeted Energy Transfer/Nonlinear Energy Sinks

Targeted Energy Transfer/Nonlinear Energy Sinks

  • Targeted Energy Transfer (TET) is an approach which imposes conditions of nonlinear resonance between interacting dynamic systems in order to achieve unidirectional energy transfer from the primary system (donor) to the secondary system (receiver).
  • Adding a local attachment that possesses essential stiffness nonlinearity (without any linear term) to the primary system may significantly alter the overall dynamic characteristics, because of the lack of a preferential resonance frequency in the (nonlinear) attachment.
  • Under certain conditions (initiated by achievement of the right energy threshold) the attachment (receiver) can engage in nonlinear resonance with a set of structural modes of the main system (donor) over a broad frequency range and act as a Nonlinear Energy Sink (NES).
  • This is contrary to the classical linear vibration absorber whose action is confined to a narrow frequency band, thus being less robust. Generally, an NES requires some inertia, essentially nonlinear stiffness and – usually – linear damping. The nonlinear stiffness enables the NES to resonate with any of the linearised modes of the primary system, whereas the damping dissipates part of the vibrational energy transferred through resonant modal interactions.
  • The phenomenon is transient and the actual scenario depends on the level and spatial distribution of the instantaneous vibration energy of the system.