US Patent 10151204 Airfoil including loose damper

An airfoil includes an airfoil body that has a leading edge and a trailing edge and a first sidewall and a second sidewall that is spaced apart from the first sidewall. The first sidewall and the second sidewall join the leading edge and the trailing edge between a radially outer end and a radially inner end. The first sidewall and the second sidewall at least partially define a cavity extending radially in the airfoil body. A damper member has a free radially inner end in the cavity and a free radially outer end in the cavity. The damper member is free-floating in the cavity.