The main experimental outcomes of this damper system(SFD) are introduced

which has laid a foundation for design application. Bistable jump depicts deep nonlinearity of SFD. Experimental results demonstraue the bi-stable jumpings of both centralized and uncentralized SFD systems and illustrate that the jump can be distinguished from an abrupt amplitude change of critical speed according to whether the mass center of the disc rotates to the opposite direction. In order to examine the structural integrity of SFD

a 256 hours life-test has been carried out. It is shown that the SFD not only exhibits quite good damping effect

but also stands the long-time test under severe working conditions.