Feasibility Study for a Composite Aircraft Fuselage Section made by an Integral Design 5th Technical Conference Swiss SAMPE Chapter Autor: Tutor: Prof. P. Ermanni / Dr. M. Zogg 25.01.2011, page 1
Table of Contents Composites for Aircraft Fuselage Structures Fuselage Section with Integral Design Cost Analysis Conclusion 25.01.2011, page 2
Composites for Aircraft Fuselage Structures fiber composites rate of the structural weight year of first flight Quelle: DLR 25.01.2011, page 3
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 25.01.2011, page 4
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, 25.01.2011, page 5
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 25.01.2011, page 6
Composites for Aircraft Fuselage Structures Existing manufacturing concepts: Airbus A350: outer skin is made of four shells riveted frame Sections *Quelle: Airbus, Aerotec 25.01.2011, page 7
Composites for Aircraft Fuselage Structures other Concepts There is a lot of effort for new manufacturing concepts Quelle: Airbus, Griess, DLR 25.01.2011, page 8
Table of Contents Composites for Aircraft Fuselage Structures Integrated Concept Cost Analysis Conclusion 25.01.2011, page 9
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 25.01.2011, page 10
Integrated Concept Two modules circular integral frames, (frame & floor beams) Skin with integrated stringers and other stiffeners (windows) 25.01.2011, page 11
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 25.01.2011, page 12
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 25.01.2011, page 13
FEM Bend up the window with integrated stringers and stiffeners is not critical. Max 0.1% strain (0.3% allowed) 25.01.2011, page 14
Table of Contents Composites for Aircraft Fuselage Structures Integrated Concept Cost Analysis Conclusion 25.01.2011, page 15
Weight and Costs lower costs through weight reduction less connections less rivets Full Name 25.01.2011, page 16
Cost Analysis Full Name 25.01.2011, page 17
Summary and Conclusions New concept in integral design Konzept FEM machbarkeit feasability was signifikates Potential bei Kosten und Gewicht only for cylindrical sections Full Name 25.01.2011, page 18
Questions martin@durrer.eu 25.01.2011, page 19
Manufacturing Formenbau: 25.01.2011, page 20
Pflichtenheft Pflichtenheft Rumpfdimensionen A320 in CFK: Durchmesser 3.96m Haut 2.5mm Stringer 1.5mm Spanten 2.5mm 25.01.2011, page 21
Assembling Bilder mit MECHANISMUS gezieltes definiertes Aufbiegen Full Name 25.01.2011, page 22