Nonlinear Aeroelastic Effects in Damaged Composite Aerospace Structures.
Abstract
Matrix micro-cracking affects the stiffness properties of composite laminates and the corresponding sectional stiffnesses, most prominantly laminates exhibiting elastic coupling. Matrix micro-cracking gives rise to nonlinear materials behavior in the presence of nonuniformly distributed crack densities. Such matrix damage appears to have little effect on basic bending-torsion flutter speed. However, this damage can induce a limit cycle behavior at airspeeds somewhat below the flutter speed. The effect of damage on the aeroelastic behavior of wing-aileron systems is found to be more pronounced. Here again flutter speeds were found to be slightly lower in the presence of damage. However, in this case, a limit cycle behavior was observed for a significant range of airspeeds below the flutter speed. Reduced fatigue life could result from this limit cycle behavior, since much higher cyclic stresses are generated thereby in the wing-aileron structure.
Document Details
- Document Type
- Technical Report
- Publication Date
- Oct 27, 1997
- Accession Number
- ADA332139
Entities
People
- O. A. Bauchau
- R. G. Loewy
Organizations
- Georgia Tech