الفهرس 
Literature ReviewOnly 14 pages are availabe for public view
 |  | from | 224 |  |  |
| | | from | 224 | | |
Abstract
Airplane Industry is one of the most important industries existing now in the world. It has been going through many phases of changing materials used in airplane manufacturing. It started with wood then metals specially aluminum, then composite materials. Also it has been going through changes in airplane size and market needs.
Through this development phases, there were a lot of research in airplane design, airplane manufacturing ways and materials, to reach lowest costs and highest passengers comfort. Composite materials had an important role in that development, as they participated in highly reducing airplane weight so reducing fuel consumption. There are a lot of different types of composite materials; they differ in mechanical and physical properties. Designer has to select from them depending on the application they are assigned for.
The process of designing an airplane consists of number of steps starting from determining the airplane mission, then estimating airplane weight and its center of gravity, then wing sizing, then selecting airplane configuration, then tail sizing, then checking airplane stability and performance.
After that a part of the airplane is chosen to be studied, which is the wing spar. The wing spar is the part that holds bending and torsion moments applied on airplane wing. Study objective is to reduce spar weight through alternating its structure or material. The study is done using Finite Element Analysis (numerical method) using Ansys software. Loads from the conceptual design phase, are assigned on the model. Constraints are max deformation at wing tip and max stress. Then verification is done for the numerical solution using analytical solution using equations from Solid Mechanics references. At the end, conclusions of the study are presented.
Results show that C section beam cannot be used in applications with bending and torsion loads like the application in this thesis. On the other hand box cross section can be used for these applications. Moreover, GFRP shows no promising results since all its cases exceed the deflection limit. Results of box spar show tip deflection of 145.3 mm, 227.8 mm and 240.5 mm in GFRP results. On the other hand, Al cases shows promising results when using box cross section. In addition, CFRP shows promising results far lower than deflection limits. Results of box spar show tip deflection of 58.5 mm, 79.1 mm and 91.1 mm.
Furthermore, estimating manufacturing and operation costs shows that using CFRP instead of Al as spar material will save about 3205 L.E. in the first year of operation. Therefore, in this case study, it can be considered the suitable material for the economic manufacturing of the spar in the airplane body, compared to Al and GFRP.