Thursday, December 8, 9:30 am in room MTH 3206, University of Maryland,
College Park
h-p Version of FEM for Reliable Analysis of Aircraft Structures
Dr. Börje Andersson
Aeronautical Research Institute of Sweden
Bromma, Sweden
ba@riscy.ffa.se
Light-weight stiffened aircraft shell structures made of aluminum and
carbon-fibre composites are designed for operation in severe environments
for decades. The most important structural criteria are design against
shell buckling and growth of small cracks (fatigue growth). Today,
aircraft structural safety rests mainly on succesful completion of large
experimental programs and to, a continously increasing extent, numerical
analysis procedures.
The steady progress in mathematics, numerical methods and computer software
and hardware, today make it possible to reliably solve many crack growth
and structural shell stability problems in early design phase.
The most important structural analysis method is the finite element method.
The most recent development of finite element method is the so called h-p
version for which a solid theoretical foundation has been developed only
the last two decades.
At the Aeronautical Research Institute of Sweden, work with h-p version of
FEM started 1984. The emphasis has been on solution of structural problems
related to aircraft design. Since 1986 the work has been performed jointly
with staff from University of Maryland (Professor Ivo Babuska et al).
Today the code STRIPE, for linear and nonlinear structural analysis,
developed during the period, is used in Swedish aircraft industry and for
research.
The outline of the seminar is
- Importance of mathematics for creation of engineering
analysis tools
- Implementational aspects of h-p version of FEM
- equation solution
- fast calculation of stiffness data
- computer architectures
- Reliable solution of real-life problems
- mesh generation for h-p version of FEM
- large problems (> 3 Mdofs)
- Analytical capabilities needed
- geometrically nonlinear analysis
- materially nonlinear analysis
- fracture mechanics analysis
- contact mechanics analysis
- rational stress analysis tools
- Extraction of engineering data
- fatigue design
- damage tolerant design (DTA)
- Practical applications
- fin, fuselage aircraft parts
- mult-site damage in thin shells
- optimal design with DTA-constraints
- Future developments
|
