Abstract: A rotor, such as a rotor of an aircraft gas turbine engine, uses damper-ring devices for damping unwanted rotor vibrations. One device has inner and outer damper rings with the outer damper ring providing ring-rotor frictional damping only at large vibrational amplitudes and with the inner and outer damper rings providing inter-ring frictional damping at both small and large vibrational amplitudes. Other devices include a damper ring and a viscoelastic layer, a hollow damper ring containing particulate matter, and a damper ring in the form of a cable made of twisted single-wire strands.

Abstract: A uniform stiffness laminated composite shell assembly includes a plurality of composite shells. The shells are made of layers of laminates of graphite-epoxy material having fibers oriented in various stacking sequences for performing different functions in the assembly. The shells are concentrically assembled in a desired sequence with some of the adjacent ones of the shells being at least equal to or greater in axial length than others thereof and with some of the shells being adapted to perform a structural load bearing function while others of the shells being adapted to perform a load transfer function. The desired sequence of shells of the composite shell assembly provides enhanced thermal insulating properties and efficient load distributing properties for enabling use of the assembly as a tube suspension in a superconductive magnet.