Feasibility Study for a Composite Aircraft Fuselage...
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www.structures.ethz.ch CENTRE OF STRUCTURE TECHNOLOGIES Martin Durrer 25.01.2011, page 1 Feasibility Study for a Composite Aircraft Fuselage Section made by an Integral Design 5th Technical Conference Swiss SAMPE Chapter Autor: Martin Durrer Tutor: Prof. P. Ermanni / Dr. M. Zogg
Transcript of Feasibility Study for a Composite Aircraft Fuselage...
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CENTRE OF STRUCTURE TECHNOLOGIESMartin Durrer
25.01.2011, page 1
Feasibility Study for a Composite Aircraft Fuselage Section
made by an Integral Design
5th Technical Conference Swiss SAMPE Chapter
Autor: Martin DurrerTutor: Prof. P. Ermanni / Dr. M. Zogg
www.structures.ethz.ch
CENTRE OF STRUCTURE TECHNOLOGIESMartin Durrer
25.01.2011, page 2
Table of Contents
Composites for Aircraft Fuselage Structures
Fuselage Section with Integral Design
Cost Analysis
Conclusion
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CENTRE OF STRUCTURE TECHNOLOGIESMartin Durrer
25.01.2011, page 3
Composites for Aircraft Fuselage Structures
Quelle: DLR
year of first flight
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ght
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CENTRE OF STRUCTURE TECHNOLOGIESMartin Durrer
25.01.2011, page 4
Composites for Aircraft Fuselage Structures
Objectives in the use of CFRP in aircraft
– reduced operating costs– weight reduction of the primary structure up to 40%*– improved fatigue behavior – no corrosion
Manufacturing as Key
– manufacturing concept• optimized tolerance design
– Example: spring-in effect• production oriented design
– tools, tool removal, rework– joining concept (rivets and/or adhesives)
*Quelle: DLR, Airbus
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CENTRE OF STRUCTURE TECHNOLOGIESMartin Durrer
25.01.2011, page 5
Composites for Aircraft Fuselage Structures
Existing manufacturing concepts:
– Boeing Dreamliner:• one piece closed ring fuselage section• outer skin with stringers in integral design• riveted frame Sections with L-shaped connection elements
Quelle: Boeing,
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CENTRE OF STRUCTURE TECHNOLOGIESMartin Durrer
25.01.2011, page 6
Composites for Aircraft Fuselage Structures
Rivets
– precise hole under clean room conditions– use of titanium or stainless steel rivets (no corrosion)– set the rivets with epoxy or sealant
Quelle: SAE, Flug Revue 9.2010, Boeing
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CENTRE OF STRUCTURE TECHNOLOGIESMartin Durrer
25.01.2011, page 7
Composites for Aircraft Fuselage Structures
Existing manufacturing concepts:
– Airbus A350:• outer skin is made of four shells• riveted frame Sections
*Quelle: Airbus, Aerotec
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CENTRE OF STRUCTURE TECHNOLOGIESMartin Durrer
25.01.2011, page 8
Composites for Aircraft Fuselage Structures
other Concepts
– There is a lot of effort for new manufacturing concepts
Quelle: Airbus, Griess, DLR
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CENTRE OF STRUCTURE TECHNOLOGIESMartin Durrer
25.01.2011, page 9
Table of Contents
Composites for Aircraft Fuselage Structures
Integrated Concept
Cost Analysis
Conclusion
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CENTRE OF STRUCTURE TECHNOLOGIESMartin Durrer
25.01.2011, page 10
Integrated Concept
Motivation:
– Reduction of production costs
– Continuing integral design• integrated frame• integrated stringers, window and door stiffeners
– better automation• fewer steps• reduced or no manual work
– Reduction of the rivets
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CENTRE OF STRUCTURE TECHNOLOGIESMartin Durrer
25.01.2011, page 11
Integrated Concept
Two modules
– circular integral frames, (frame & floor beams)– Skin with integrated stringers and other stiffeners (windows)
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CENTRE OF STRUCTURE TECHNOLOGIESMartin Durrer
25.01.2011, page 12
Integrated Concept
Assembling:
– integral frame– skin with integrated stringers– bending up of the shell– closing and bonding of the structure– closing of the longitudinal cut
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CENTRE OF STRUCTURE TECHNOLOGIESMartin Durrer
25.01.2011, page 13
Compared to Existing Concepts
Benefits
– Higher level of automation is possible• finished interior structure• Pre-assembly of interior partly possible
– Saving a further 1,500 rivets per frame (compared to Boeing 787 design with a diameter of 4m like A320)
• 500 skin – connecting elements• 1000 connecting elements – frames
– Boeing 787 already uses 40,000 rivets per Section less than a conventional fuselage section because of integrated stringers (10 frames per Section)
Challanges
– No more closed-shell– Additional bonding step
*Quelle: Boeing
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CENTRE OF STRUCTURE TECHNOLOGIESMartin Durrer
25.01.2011, page 14
FEM
Bend up the window with integrated stringers and stiffeners is not critical.
– Max 0.1% strain (0.3% allowed)
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CENTRE OF STRUCTURE TECHNOLOGIESMartin Durrer
25.01.2011, page 15
Table of Contents
Composites for Aircraft Fuselage Structures
Integrated Concept
Cost Analysis
Conclusion
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Weight and Costs
lower costs through weight reduction
– less connections– less rivets
CENTRE OF STRUCTURE TECHNOLOGIESFull Name
25.01.2011, page 16
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Cost Analysis
CENTRE OF STRUCTURE TECHNOLOGIESFull Name
25.01.2011, page 17
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Summary and Conclusions
New concept in integral design
– Konzept– FEM machbarkeit– …
– feasability was
– signifikates Potential bei Kosten und Gewicht
– only for cylindrical sections
CENTRE OF STRUCTURE TECHNOLOGIESFull Name
25.01.2011, page 18
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CENTRE OF STRUCTURE TECHNOLOGIESMartin Durrer
25.01.2011, page 19
Questions
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CENTRE OF STRUCTURE TECHNOLOGIESMartin Durrer
25.01.2011, page 20
Manufacturing
Formenbau:
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CENTRE OF STRUCTURE TECHNOLOGIESMartin Durrer
25.01.2011, page 21
Pflichtenheft
Pflichtenheft
Rumpfdimensionen A320 in CFK:
– Durchmesser 3.96m– Haut 2.5mm– Stringer 1.5mm– Spanten 2.5mm
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Assembling
Bilder mit MECHANISMUS
gezieltes definiertes Aufbiegen
CENTRE OF STRUCTURE TECHNOLOGIESFull Name
25.01.2011, page 22
