Date of Graduation
Statler College of Engineering and Mineral Resources
Mechanical and Aerospace Engineering
The aeroelasticity of composite wings is becoming an increasingly researched topic in aircraft design, as designers continue to replace aluminum alloy components with those made of composite materials because of their favorable strength-to-weight ratio, fatigue characteristics, and corrosion resistance. Additionally, the bending-torsion coupling exhibited by composite laminates readily allow for the aeroelastic optimization of an aerodynamic structure through the process of aeroelastic tailoring. Wings made of composites materials, however, are more vulnerable to shear deformation.
The objective of the present research is to study the divergence and flutter characteristics of composite plate wings using a higher-order shear deformation theory (HSDT) with higher-order finite element modeling (FEM). This is expected to clarify whether HSDT offers any meaningful advantage over the more widely used first order shear deformation theory (FSDT) and to determine how the application of an h-p version conforming plate element improves computational aeroelastic modeling.
A new higher-order composite plate element, called MONNA, is introduced and coupled with the vortex lattice, doublet lattice, and doublet point aerodynamic panel method models. The novel element is conforming, but it does not directly have the capacity for quadrilateral transformation. The higher-order plate element demonstrates better aeroelastic convergence and accuracy relative to traditional elements. Negligible difference is shown between FSDT and HSDT for a variety of plate materials and thicknesses. A parametric study is performed, revealing the divergence-flutter tradeoff associated with change in ply orientation along with other insights into aeroelastic tailoring. Overall, the HSDT is concluded to be superfluous in aeroelastic plate analysis. The practicality of the new higher-order element is found to be limited in the field of aeroelasticity, but it may be more practical in other engineering applications.
Haught, Justin A., "Aeroelasticity of Composite Plate Wings using HSDT and Higher-Order FEM" (2020). Graduate Theses, Dissertations, and Problem Reports. 7547.