In gas turbine engines, turbine blades extract energy from the hot gas
and transmit it to the disc. These blades are attached to the disc
typically through multi-lobed firtrees. The choice of type of
fastening arrangement depends on the force being transmitted from the
blade to disc. In aero gas turbine engines, turbine discs are
classified as Class I critical components because the failure of discs
leads to complete failure of the engine itself. It has been observed
in cyclic spin tests and in functional engines that one of the modes
of failure of the blade-disc arrangement is failure by fretting
fatigue which occurs when two components are held in contact through
application of normal load, and oscillatory tangential forces are
applied resulting in surface damage which, in combination with high
stress, can lead to failure. The solving of the fretting fatigue
problem involves the obtaining of the stress field at the contact
region and the assessment of the damage accumulated over a given
number of cycles and, consequently, the assessment of cycles to
failure due to fretting fatigue. The objective of this work is to
efficiently model fretting fatigue of turbine blade-disc multi-lobe
firtree joint which also takes into consideration load history
effects. Effects of dissimilar materials and temperature shall also be
included.