Περίληψη: | The purpose of this thesis is the design of the wing of a MALE class (Medium Al-
titude Long Endurance) unmanned aircraft vehicle. Initially, a survey is conducted
with the aim of collecting and comparing the performance of some unmanned aerial
vehicles which can also be characterized as "State of the art" in the field of UAVs.
Parameters such as flight speed, range, and payload are thus selected for the UAV
under design to be competitive. Afterwards in the conceptual design phase, the
calculations of the weights through an iterative process are conducted. Then the
wing load and the required thrust are selected through a graphical method based
on the FAR-23 airworthiness regulations. In the next phase, the design focuses on
the geometry of the wing, where basic design parameters will be selected for the
top view of the wing and airfoil. Additionally, through a methodology, based on
FAR-23 regulations, the maximum load factor is calculated. After the conceptual
design is complete, the wing is designed in CAD software. Then, proceeding to the
structural design of the wing, three different candidate structures will be examined
and compared with each other in terms of not only weight and stiffness, but also
issues related to manufacturing and assembly. The next phase of the study is the
aerodynamic analysis of the wing through FLUENT software and the finite element
method. The purpose of the aerodynamic analysis is to verify the aerodynamic be-
haviour but also to calculate the flight loads developed on the wing surfaces for their
use in structural analysis. The aerodynamic loads are transferred and applied to the
wing surfaces in the structural analysis phase through the FSI (Fluid Structure Inter-
action) method. Initially, it is chosen for each of the three structural analyzes to as-
sign composite materials. After the forces are transferred and the structural analysis
of each scenario is done, the models in which the structures are exclusively designed
from composite materials are compared with the corresponding ones designed from
aluminium alloy, so that conclusions can be drawn about the effectiveness in re-
ducing the weight and the very good mechanical behaviour of composite materials.
Finally, a study related to the manufacturing and assembly of each structure so that
useful conclusions can be drawn about which of the three structures is feasible and
achievable in terms of construction.
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