Numerical Parametric Stress Analysis of the TF-30 Turbine Engine Third-Stage Fan-Blade/Disk Dovetail Region.
Abstract
A two-dimensional finite element parametric analysis was conducted for the disk/blade dovetail region of the TF-30 turbine engine, assuming purely radial (centrifugal) loading of the blade. A graphical boundary matching procedure was used to determine a likely disk/blade interface force distribution. This distribution produced a stress concentration factor (SCF) of 5.3 in the disk fillet, relative to the average stress in the neck section of the disk. In addition, the SCF was found to decrease with decreasing interface friction. Parametric modification of the disk fillet resulted in a maximum SCF reduction of 27%, achieved with a fillet radius of three times the present one. For all studied combinations of interface force distribution, coefficient of friction and fillet geometry the point of maximum tensile stress occurred farther into the fillet (away from the contact region) than the point at which cracks appear to initiate (near, or just into the inboard edge of the contact area). However, different combinations of interface force and fillet geometry result in different degrees of spread of the tensile stress concentration from the fillet area into the contact area. Finally, the effects of some assumed interface force perturbations due to non-radial (non-centtrifugal) loading are discussed. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Jan 01, 1978
- Accession Number
- ADA051299
Entities
People
- L. A. Beaubien
Organizations
- United States Naval Research Laboratory