Feasibility Study for a Composite Aircraft Fuselage Section made by an Integral Design

Transcription

1 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 , page 1

2 Table of Contents Composites for Aircraft Fuselage Structures Fuselage Section with Integral Design Cost Analysis Conclusion , page 2

3 Composites for Aircraft Fuselage Structures fiber composites rate of the structural weight year of first flight Quelle: DLR , page 3

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 , page 4

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, , page 5

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 , Boeing , page 6

7 Composites for Aircraft Fuselage Structures Existing manufacturing concepts: Airbus A350: outer skin is made of four shells riveted frame Sections *Quelle: Airbus, Aerotec , page 7

8 Composites for Aircraft Fuselage Structures other Concepts There is a lot of effort for new manufacturing concepts Quelle: Airbus, Griess, DLR , page 8

9 Table of Contents Composites for Aircraft Fuselage Structures Integrated Concept Cost Analysis Conclusion , page 9

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 , page 10

11 Integrated Concept Two modules circular integral frames, (frame & floor beams) Skin with integrated stringers and other stiffeners (windows) , page 11

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 , page 12

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 , page 13

14 FEM Bend up the window with integrated stringers and stiffeners is not critical. Max 0.1% strain (0.3% allowed) , page 14

15 Table of Contents Composites for Aircraft Fuselage Structures Integrated Concept Cost Analysis Conclusion , page 15

16 Weight and Costs lower costs through weight reduction less connections less rivets Full Name , page 16

17 Cost Analysis Full Name , page 17

18 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 , page 18

19 Questions , page 19

20 Manufacturing Formenbau: , page 20

21 Pflichtenheft Pflichtenheft Rumpfdimensionen A320 in CFK: Durchmesser 3.96m Haut 2.5mm Stringer 1.5mm Spanten 2.5mm , page 21

22 Assembling Bilder mit MECHANISMUS gezieltes definiertes Aufbiegen Full Name , page 22