Nonlinear Dynamic Analysis of a Thermally Buckled Aircraft Panel Using NNMs

• Published in: Shock & Vibration, Aircraft/Aerospace, Energy Harvesting, Acoustics & Optics, Volume 9 pp. 59 - 69
• Main Authors: Jarman, Lucas M., VanDamme, Chris, Allen, Mathew S.
• Format: Book Chapter
• Language: English
• Published: Switzerland River Publishers 2017; Springer International Publishing AG; Springer International Publishing
• Edition: 1
• Series: Conference Proceedings of the Society for Experimental Mechanics Series
• Subjects: Acoustic & sound engineering; Aerospace & aviation technology; Dynamics & vibration; Geometric nonlinearity; Implicit condensation and expansion; Nonlinear normal modes; Reduced order modeling; Thermal expansion; Thermal expansion; Nonlinear normal modes; Geometric nonlinearity; Implicit condensation and expansion; Reduced order modeling
• ISBN: 3319547348; 9783319547343; 9783319854670; 3319854674
• ISSN: 2191-5644; 2191-5652
• DOI: 10.1007/978-3-319-54735-0_7

Many thin walled structures experience a combination of static thermal stress and large amplitude dynamic loads. From a dynamic perspective, the heating can change both the linear and nonlinear properties of the system so that completely different responses may be obtained (e.g. they may snap through rather than exhibiting a simple hardening nonlinearity). This work uses the "cold modes" approach to create various reduced order models of one panel from a concept hypersonic vehicle; heating is assumed to change only the linear natural frequencies of the panel, but not the mode shapes or geometrically nonlinear effects. The resulting reduced order models are studied by computing their nonlinear normal modes and their response subject to a random dynamic pressure. The comparisons reveal that much can be inferred about the response from the nonlinear modes.