Vibration damper for a gas turbine

摘要

A vibration damper 46 for a gas turbine engine has convergent friction surfaces 48a and 48b and is located radially inward of the platforms 20a and 20b of two adjacent turbine blades. The angle subtended by the friction surfaces 48a and 48b is smaller than that subtended by the angled faces 22a and 22b associated with the platforms 20a and 20b. The centre of mass of the damper 46 lies in a plane bisecting the angle subtended by the friction surfaces 48a and 48b. In use the damper 46 is urged radially outwards by centrifugal force so that at least one of the friction surfaces 48a and 48b makes planar contact with at least one of the angled faces 22a and 22b. Vibrational energy is dissipated by the resultant sliding movement between the friction surfaces 48a and 48b and the angled faces 22a and 22b. A secondary vibration damping mechanism arises from the oscillation of the damper 46 between the platforms 20a and 20b.