Analytical Study of Mistuning/Friction/Aerodynamics Interaction in a Bladed Disk Assembly

Abstract

The analytical technique is shown to be valid for the computation of the statistics of blade's vibratory amplitude when the distributions of modal parameters of a mistuned bladed disk assembly are non-gaussian. The results from the analytical technique are compared with those from numerical simulations for triangular and uniform distributions. It was found that the probability density function of the amplitude is insensitive to the types of mistuning distributions. Next, an analytical technique was developed to efficiently compute the probability density function of the maximum amplitude on a mistuned bladed assembly. This technique uses the direct taylor series expansion in terms of the perturbation in an amplitude as a function of perturbations in modal stiffnesses. The validity of the techniques has been corroborated by comparison with the results from numerical simulations. Lastly, the statistic of the forced response of a structurally and aerodynamically coupled bladed disk assembly were computed efficiently by the analytical technique. The results from the analytical technique agree well with those from numerical simulations. The effects of the following parameters on the statistics of the maximum amplitude were studied; For the aerodynamic couplings among blades, the fluid density and the cascade stagger angle. Keywords: Cascade structures; Subsonic flow; Turbine blades.

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Document Details

Document Type
Technical Report
Publication Date
Feb 06, 1989
Accession Number
ADA211139

Entities

People

  • Alok Sinha
  • Shing Chen

Organizations

  • Pennsylvania State University

Tags

Communities of Interest

  • Air Platforms
  • Materials and Manufacturing Processes

DTIC Thesaurus Topics

  • Computer Programs
  • Differential Equations
  • Dynamic Response
  • Equations
  • Frequency
  • Gaussian Distributions
  • Mechanical Engineering
  • Probability
  • Probability Density Functions
  • Probability Distributions
  • Random Variables
  • Resonant Frequency
  • Statistics
  • Steady State
  • Stochastic Processes
  • Turbines
  • Two Dimensional

Fields of Study

  • Physics

Readers

  • Aerodynamics.
  • Statistical inference.
  • Structural Dynamics.