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Design and Analysis of an Integrated Three- Bay Thermoplastic Composite Wingbox



The design of a multi-part aerospace structural component, such as a wingbox, is a challenging process because of the complexity arising from assembly and integration, and their associated limitations and considerations. In this study, a design process of a stiffeners-integrated variable stiffness three-bay wingbox is presented. The wingbox has been designed for a prescribed buckling and post-buckling performance (a prescribed real testing scenario) and made from thermoplastic composite material system (Carbon-PEEK) with the total length of three meters. The stiffeners and spars are integrated into the top and bottom panels of the wingbox resulting a single-piece blended structure with no fasteners or joints. The bottom skin also has an elliptical cut-out for access purposes. The composite tows are steered around this cutout for strain concentration reduction purposes. The fiber/tow steering in the top skin bays (compression side) has also been considered for improved compression-induced buckling load carrying capacity. The proposed design has been virtually verified via high fidelity finite element analysis.


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V. Oliveri, G. Zucco, D. Peeters, G. Clancy, R. Telford, M. Rouhi, R. OHiggins

C. McHale, T. Young, and P. M.Weaver. Design, manufacture and test of an in-situ consolidated

thermoplastic variable-stiffness wingbox. AIAA Journal, 57(4):1671–1683,

M.W. Hyer and H.H. Lee. The use of curvilinear fiber format to improve buckling resistance

of composite plates with central circular holes. Composite Structures, 18:239–261,

Z. G¨urdal and R. Olmedo. In-plane response of laminates with spatially varying fiber

orientations-variable stiffness concept. AIAA Journal, 31(4):751–758, 1993.

S.B. Biggers and S.S. Fageau. Shear buckling response of tailored rectangular composite

plates. AIAA Journal, 32(5):1100–1103, 1994.

D. Peeters, S. Hesse, and M. M. Abdalla. Stacking sequence optimisation of variable

stiffness laminates with manufacturing constraints. Composite Structures, 125:596 –

, 2015.

A. Madeo, R.M.J. Groh, G. Zucco, P.M.Weaver, G. Zagari, and R. Zinno. Post-buckling

analysis of variable-angle tow composite plates using koiter’s approach and the finite

element method. Thin-Walled Structures, 110:1 – 13, 2017.

R.M.J. Groh and P. M. Weaver. Buckling analysis of variable angle tow, variable thickness

panels with transverse shear effects. Composite Structures, 107:482–493, 2014.

B. H. Coburn and P. M.Weaver. Buckling analysis, design and optimisation of variablestiffness

sandwich panels. International Journal of Solids and Structures, 96:217 – 228,

S. C. White and P. M. Weaver. Towards imperfection insensitive buckling response of

shell structures-shells with plate-like post-buckled responses. The Aeronautical Journal,

(1224):233–253, 2016.

R. Vescovini, V. Oliveri, D. Pizzi, L. Dozio, and P. M. Weaver. A semi-analytical approach

for the analysis of variable-stiffness panels with curvilinear stiffeners. International

Journal of Solids and Structures, 188-189:244 – 260, 2020.

V. Oliveri and A. Milazzo. A rayleigh-ritz approach for postbuckling analysis of variable

angle tow composite stiffened panels. Computers & Structures, 196:263 – 276, 2018.

G. Sciascia, V. Oliveri, A. Milazzo, and P. M.Weaver. Ritz solution for transient analysis

of variable-stiffness shell structures. AIAA Journal, 58(4):1796–1810, 2020.

D. Jegley, B. Tatting, and Z. G¨urdal. Tow-steered panels with holes subjected to compression

or shear loading. In 46th AIAA/ASME/ASCE/AHS/ASC Structures, Structural

Dynamics and Materials Conference, page 2081, 2005.

D. Peeters, G. Clancy, V. Oliveri, R. O’Higgins, D. Jones, and P. M. Weaver.

Thermoplastic composite stiffener design with manufacturing considerations. 2018

AIAA/ASCE/AHS/ASC Structures, Structural Dynamics, and Materials Conference,

G. Zucco, M. Rouhi, V. Oliveri, E. Cosentino, R. O’Higgins, and P. M. Weaver. Design

of a composite panel with continuous tow steering around an elliptical cut-out.

Submitted to ASC 36TH TECHNICAL CONFERENCE, Sept. 19-22, 2021, Texas A&M

University, 2021.


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