TY - GEN
T1 - Folding of flexible hinges for aircraft wingtips and wind turbine blades
AU - Bowen, Aileen G.
AU - Zucco, Giovanni
AU - Weaver, Paul M.
N1 - Publisher Copyright:
© 2021, American Institute of Aeronautics and Astronautics Inc, AIAA. All Rights Reserved.
PY - 2021
Y1 - 2021
N2 - The design of localized and controlled compliance in thin-walled structures by exploiting unstable behavior during bending, i.e. Brazier phenomena, has potential for dispensing with mechanically-hinged structures. This morphing hinge-free technology offered by flexible hinges saves weight, eliminates friction-related problems and reduces part-count. Two novel applications of flexible hinges are considered herein. The first, the folding of aircraft wingtips to increase wing aspect-ratio while complying with airport space restrictions. The second, the folding of wind-turbine blades with the aim of facilitating large blade transportation. In this study, we focus on optimizing the folding process of orthotropic symmetric crossply flexible hinges with airfoil cross-section by minimizing their folding load, hence reducing folding-induced stress. To date, few works appear to study Brazier phenomena for airfoils, contrasting with extensive analytical and experimental research dedicated to circular crosssections. For the purpose of minimizing the folding load, we examine whether available analytical solutions for orthotropic circular cross-section are applicable to airfoil cross-sections. The assessment is based on finite element analysis. Furthermore, since length is an important design consideration for the applications under consideration and the folding load is lengthdependent, we provide insights into the effects of length on the folding load.
AB - The design of localized and controlled compliance in thin-walled structures by exploiting unstable behavior during bending, i.e. Brazier phenomena, has potential for dispensing with mechanically-hinged structures. This morphing hinge-free technology offered by flexible hinges saves weight, eliminates friction-related problems and reduces part-count. Two novel applications of flexible hinges are considered herein. The first, the folding of aircraft wingtips to increase wing aspect-ratio while complying with airport space restrictions. The second, the folding of wind-turbine blades with the aim of facilitating large blade transportation. In this study, we focus on optimizing the folding process of orthotropic symmetric crossply flexible hinges with airfoil cross-section by minimizing their folding load, hence reducing folding-induced stress. To date, few works appear to study Brazier phenomena for airfoils, contrasting with extensive analytical and experimental research dedicated to circular crosssections. For the purpose of minimizing the folding load, we examine whether available analytical solutions for orthotropic circular cross-section are applicable to airfoil cross-sections. The assessment is based on finite element analysis. Furthermore, since length is an important design consideration for the applications under consideration and the folding load is lengthdependent, we provide insights into the effects of length on the folding load.
UR - http://www.scopus.com/inward/record.url?scp=85100310092&partnerID=8YFLogxK
U2 - 10.2514/6.2021-0204
DO - 10.2514/6.2021-0204
M3 - Conference contribution
AN - SCOPUS:85100310092
SN - 9781624106095
T3 - AIAA Scitech 2021 Forum
SP - 1
EP - 23
BT - AIAA Scitech 2021 Forum
PB - American Institute of Aeronautics and Astronautics Inc, AIAA
T2 - AIAA Science and Technology Forum and Exposition, AIAA SciTech Forum 2021
Y2 - 11 January 2021 through 15 January 2021
ER -