@INPROCEEDINGS{gotting2004systematic,
  author = {G{\"o}tting, Florian and Sextro, Walter and Panning, Lars and Popp,
	Karl},
  title = {Systematic mistuning of bladed disk assemblies with friction contacts},
  booktitle = {Proceedings of ASME TURBO Expo, Power for Land, Sea, and Air},
  year = {2004},
  volume = {6},
  number = {GT2004-53310},
  pages = {257-267},
  month = {June},
  organization = {ASME},
  abstract = {In turbomachinery, friction contacts are widely used to reduce dynamic
	stresses in turbine blades in order to avoid expensive damages. As
	a result of energy dissipation in the friction contacts the blade
	vibration amplitudes are reduced. In case of so-called friction dampers,
	which are pressed on the platforms of the blades by centrifugal forces,
	the damping effect can be optimized by varying the damper mass. This
	optimization can be done by means of a simulation model applying
	the so-called component mode synthesis and the Harmonic Balance Method
	to reduce computation time. It is based on the modal description
	of each substructure. In a real turbine or compressor blading great
	differences in the magnitude of the individual blade amplitudes occur
	caused by unavoidable mistuning of all system parameters like contact
	parameters and natural frequencies of the blades. It may happen that
	most of the blades experience only small stresses whereas a few blades
	experience critical stresses. Therefore, it is necessary to consider
	mistuning for all system parameters to simulate the forced response
	of bladed disk assemblies with friction contacts. For a mistuned
	bladed disk the complete system has to be modeled to calculate the
	dynamic response. In practice, usually the standard deviations instead
	of the distributions of the system parameters are known. Therefore,
	Monte-Carlo simulations are necessary to calculate the forced response
	of the blades for given mean values and standard deviations of the
	system parameters. To reduce the computational time, an approximate
	method has been developed and extended for small and moderate standard
	deviations of the system parameters to calculate the distribution
	and the envelopes of the frequency response functions for statistically
	varying system parameters, in the following called statistical mistuning.
	The approximate method is based on a sensitivity analysis and the
	assumption of a Weibull distribution of the vibration amplitudes
	of the blades. Both, the approximate method and the assumption of
	a Weibull distribution of the vibration amplitudes are validated
	by Monte-Carlo simulations. By these investigations the influence
	of different arrangements of the system parameters for given mean
	values and standard deviations of the vibration amplitudes of the
	blades can be determined, too. For the present investigations only
	a small influence of the arrangement of blades with respect to their
	natural frequencies has been observed. On the other hand, an intentional
	mistuning of the damper masses and the natural frequencies of the
	blades in a systematic way, in the following called systematic mistuning,
	can be investigated to reduce the amplitudes of the system. The simulation
	results of a systematic mistuning has been validated by a test rig
	with a rotating bladed disk assembly with friction dampers. The investigations
	show a good agreement between the simulations and the measurements
	but only a slight decrease of the maximum amplitudes in case of a
	systematic mistuning.
	
	Copyright {\copyright} 2004 by ASME},
  keywords = {Friction, Disks},
  owner = {K. Agbons jr},
  timestamp = {2013.11.23}
}