Rapid Fatigue Life Projection for Thermal and Acoustic Loads
Abstract
Report developed under an SBIR Phase I contract for topic AF02-244. The focus of this investigation is on the prediction of the fatigue life of aircraft panels subjected to the combination of a strong random acoustic excitation and to steady thermal effects. A novel parametric model for the probability density function of the ranges (displacement or stress) is proposed and is validated using a set of 57 time histories of displacement and stresses. These time histories correspond to the response of a single well Duffing oscillator, the displacements and stresses of a NASTRAN plate model that is either buckled or unbuckled and subjected to an acoustic excitation at either normal or grazing incidence. The matching of the exact distribution of ranges and its model is at least very good in all 57 cases studied. The dependency of the five parameters of the model on the spectral moments of the response is clarified to enable a direct prediction of the fatigue life. A reliable approximation of three of the five parameters of the stress distribution model is obtained that involves the mean and spectral moments of the stress process.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jul 01, 2003
- Accession Number
- ADA420786
Entities
People
- D. D. Liu
- M. P. Mignolet
- P. C. Chen
- Xiaowei Gao