【摘 要】
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Targeted energy transfer is studied as two-dimensional wing coupled with two Nonlinear Energy Sinks(NESs)under freestream by numerical methods,it is feasible to partially or even completely suppress a
【机 构】
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School of Energy and Power Engineering,Xi'an Jiaotong University,Xi'an 710049,P.R.China
论文部分内容阅读
Targeted energy transfer is studied as two-dimensional wing coupled with two Nonlinear Energy Sinks(NESs)under freestream by numerical methods,it is feasible to partially or even completely suppress aeroelastic instability by passively transferring vibration energy from the wing to the NES in a one-way irreversible fashion,and the relationship between the vibration suppression and Targeted Energy Transfer(TET)of the system is analyzed in detail.First,the model of the coupling system,which includes heave and pitch motions,is presented,and the NESs are located at the leading edge and trailing edge(NES1 and NES2)separately.Then,the vibrations suppressed by NESs are also investigated from the viewpoint of energy transfer etc.,and the Resonance Captures(RCs)in the nonlinear coupling system are studied using spectrum analysis.Furthermore,the ensuing TET through the modes of wing(Heave and Pitch)and the NESs are discussed in detail.The NESs absorb and dissipate a significant portion of energy fed from the flow to the wing,and the results show that the NESs could absorb the energy from every single motion of the wing,and the TET and RCs between modes can be more available in the coupling system.Therefore,the TET is more efficient between the wing and NESs.It leads to the increase of the critical velocity of freestream under which the nonlinear vibration of the wing can be suppressed by NESs effectively.
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