Structural optimization of a jet trainer wing structure under strength and stiffness related constraints

Download
2020-9
Adıgüzel, Ozan
This thesis presents structural optimization studies for a jet trainer aircraft wing structure. The main purpose is to select the most convenient rib/spar layout for T-38 wing like geometry which consists of metallic and composite components by using a finite element modeling and analysis tool of MSC NASTRAN optimization capabilities. In this study, in order to decrease the number of design variables and as well as to be able to obtain smooth thickness transitions between adjacent zones, design variable linking method is used by applying different shape functions. First of all, after creating the outer geometry in CATIA, the finite element model (FEM) is prepared using MSC PATRAN. Similarly, all design zones where design variables are free to change are designated. To be able to link the thicknesses of the components to each other with regards to their locations on the wing, all coordinates of design zones are transformed to natural coordinate system as their center points are positioned as located between 0 and 1 in span-wise direction and -0.5 and 0.5 in chord-wise direction using scripts coded in Python. Aerodynamic loads are then calculated by using MSC FLDS (FlightLoads) tool and summed in predefined monitor stations to distribute onto the structure using rigid body elements. Obtained shear force and bending moment distributions are also compared with another method called as Schrenk’s Approximation. In the optimization studies, thicknesses of the metallic structures and principal composite ply thicknesses are considered as design variables. There are five design constraints which are von Mises stress for the metallic structures, failure index for strength check of composite structures, global buckling, damping and natural frequencies which are used to control the flutter speed. The objective in this research is to obtain a minimum weight in design while providing predefined constraints via investigating various design candidate geometries having different layouts but same outer geometry. Finally, by using the scripts developed within this thesis study, the design variable linking method used according to the locations of the design zones become suitable also for the Nastran Sol 200 users.

Suggestions

Structural analysis of a jet trainer cockpit
Altuğ, Muhittin Nami; Şahin, Melin; Department of Aerospace Engineering (2011)
This thesis presents structural analysis of a cockpit of a jet trainer type aircraft and the correlation studies performed by using ground pressurisation test results. For this purpose, first the response of the complex integrated fuselage structure is investigated under the complex type cabin pressure load. Then, cockpit part of the fuselage structure is modelled using commercial finite element software MSC/PATRAN® and MSC/NASTRAN®. The finite element model (FEM) of the cockpit structure is improved by the...
Structural optimization of composite and aluminum horizontal tail plane of a helicopter
Arpacıoğlu, Bertan; Kayran, Altan; Department of Aerospace Engineering (2019)
This thesis presents structural optimization studies of aluminum and composite material horizontal tail plane structure of a helicopter by using MSC.NASTRAN optimization capabilities. Structural design process starts from conceptual design phase, and structural layout design is performed by using CATIA. In the preliminary design phase, study focuses on minimum weight optimization with multiple design variables and similar constraints for both materials. Aerodynamic load calculation is performed using ANSYS ...
Manufacturing and structural analysis of a lightweight sandwich composite UAV wing
Turgut, Tahir; Kayran, Altan; Department of Aerospace Engineering (2007)
This thesis work deals with manufacturing a lightweight composite unmanned aerial vehicle (UAV) wing, material characterization of the composites used in the UAV wing, and preliminary structural analysis of the UAV wing. Manufacturing is performed at the composite laboratory founded in the Department of Aerospace Engineering, and with hand lay-up and vacuum bagging method at room temperature the wing is produced. This study encloses the detailed manufacturing process of the UAV wing from the mold manufactur...
COMPARATIVE STRUCTURAL OPTIMIZATION STUDY OF COMPOSITE AND ALUMINUM HORIZONTAL TAIL PLANE OF A HELICOPTER
Arpacıoğlu, Bertan; Kayran, Altan (2019-11-11)
This work presents structural optimization studies of aluminum and composite material horizontal tail plane of a helicopter by using MSC. NASTRAN SOL200 optimization capabilities. Structural design process starts from conceptual design phase, and structural layout design is performed by using CATIA. In the preliminary design phase, study focuses on the minimum weight optimization with multiple design variables and similar constraints for both materials. Aerodynamic load calculation is performed using ANSYS ...
Bir jet eğitim uçağı kokpitinin yapısal analizleri
Altuğ, Muhittin Nami; Şahin, Melin (null; 2012-06-20)
Bu çalışmada, bir jet eğitim uçağı kokpitinin MSC/PATRAN® ve MSC/NASTRAN® ticari sonlu elemanlar yazılımları kullanılarak modellenmesi, kokpite ait bu sonlu elemanlar modelinin yapısal analizleri ve yer basınçlandırma test sonuçları ile korelasyonu çalışmaları anlatılmaktadır. Söz konusu yer basınçlandırma testleri TUSAŞ tesislerinde gerçekleştirilmiştir.
Citation Formats
O. Adıgüzel, “Structural optimization of a jet trainer wing structure under strength and stiffness related constraints,” M.S. - Master of Science, Middle East Technical University, 2020.