Akademik Veri Yönetim Sistemi
54th AIAA/ASME/ASCE/AHS/ASC Structures, Structural Dynamics and Materials Conference, Boston, MA, Amerika Birleşik Devletleri, 8 - 11 Nisan 2013, (Tam Metin Bildiri)
This study presents a novel computational framework to improve life prediction capabilities for hypersonic aerospace platforms where evaluating the performance of these structures in extreme environments remains a challenge. Here, thermo-mechanical loading histories determined from analyses that couple aerodynamic loads and structural deflections drive high-fidelity continuum models of the structural member, and results from the continuum model in turn drive critical-plane models of fatigue crack nucleation and growth. This approach readily enables complex features of the loading, geometry, and material response to be incorporated by the structural response and life predictions. Results shown here demonstrate the capabilities of this framework, including: representative thermomechanical and acoustic loadings from ascent to cruise conditions through to descent, the full structural response history, and damage indications that incorporate the full thermocyclic history. Preliminary studies on a challenge structural panel indicate that the ascent and descent phases of the flight profile represent the primary drivers for large residual de ections (on the order of the skin thickness), that remain present in subsequent flights and that may degrade aerodynamic and structural performance. Furthermore, the highly cyclic and transient response present in the acoustic loading phase contributes strongly to localized fatigue damage. © 2013 by James C. Sobotka, Alpay Oral, and Adam J. Culler.