基于磁荷叠加增强的磁扭负刚度低频隔振研究OA

The low-frequency torsional vibration,which can not only reduce the power transmission efficiency of the shaft structures,but also threaten the operation safety of them,has been the research hotspot in the field of low-frequency vibration control.As the existing negative stiffness mechanism employed for low-frequency torsional isolation in shafts suffers from the strong nonlinearity and low negative stiffness,the design method of torsional vibration isolator with high magnetic torsional negative stiffness is proposed via magnetic charge superposition.The high magnetic tor-sional negative stiffness composed of tiles magnetized circumferentially is connected with plane spiral spring in parallel to analyze the low-frequency torsional isolation performance of the shaft structures.Referring to the magnetic charge model,the nonlinear torque and torsional negative stiffness of the High Magnetic Torsional negative Stiffness spring(HMTS)are derived,and then demonstrated via the numerical simulation of COMSOL finite element software in com-parison with that of the traditional magnetic negative stiffness array.Besides that,the mechanical properties of plane spiral spring are also investigated using Ansys Workbench.With the effects of above analysis,the governing equa-tions of the proposed isolator can be established,and relevant low-frequency isolation performance is studied with har-monic balance approach.A test rig of the isolator is set up to determine its low-frequency torsional isolation perfor-mance.The results show that the magnitude of high magnetic torsional negative stiffness spring is twice as high as that of the traditional magnetic negative stiffness ones,which can significantly broaden the isolation bandwidth as well.