تحلیل غیرخطی فلاتر جسم آزاد در هواپیما با بال منعطف

نوع مقاله : مقاله پژوهشی

نویسندگان

1 دانشجوی دکتری / دانشکده مهندسی هوافضا، دانشگاه خواجه نصیرالدین طوسی

2 عضو هیات علمی / دانشکده مهندسی هوافضا، دانشگاه خواجه نصیرالدین طوسی

چکیده

در هواپیماهای دارای بال منعطف با نسبت منظری بالا، امکان جفت شدن مودهای دینامیک پرواز و آیروالاستیسیته وجود دارد. این جفت شدن می‌تواند منجر به پدیده فلاتر جسم آزاد ‌شود که موضوع مورد بحث در این مقاله می‌باشد. در مطالعه حاضر از فرض دینامیک پرواز صفحه‌ای و مدل هواپیمای کامل با بال انعطاف‌پذیر استفاده شده است. در بال منعطف و دارای نسبت منظری بالا، اثر عبارات غیرخطی در پاسخ دینامیکی هواپیما قابل صرفنظر نیست، از این رو برای مدل سازی در بخش سازه از مدل تیر اویلر برنولی غیرخطی تعمیم یافته با درجات آزادی خمش-خمش-پیچش و در بخش آیرودینامیک از مدل آیرودینامیک ناپایا بر پایه تابع وگنر به همراه مدل استال استاتیکی استفاده شده است. سپس مدل ارائه شده صحت سنجی شده و از جنبه‌های مختلف از قبیل رفتار پایداری، دامنه نوسان سیکل حد پس از وقوع ناپایداری های فلاتر جسم آزاد و فلاتر متعارف، آنالیز حساسیت و رفتار زیربحرانی مورد مطالعه قرار گرفته است.

کلیدواژه‌ها

موضوعات


عنوان مقاله [English]

Nonlinear body-freedom flutter analysis in aircraft with the flexible wing

نویسندگان [English]

  • Salman Shafaghat 1
  • Mohammadali Noorian 2
  • saeid irani 2
1 Faculty of Aerospace Engineering, K N Toosi University of Technology
2 K. N. Toosi University of technology
چکیده [English]

In aircraft with flexible high aspect ratio wings, it is possible to couple flight dynamics modes and aeroelasticity. This coupling can lead to the body-freedom flutter (BFF) phenomenon, which is the subject of this article. In this study, the planar flight dynamics assumption and the model of a complete aircraft with flexible wings have been used. In this type of aircraft, due to the high aspect ratio of the wings, the effects of nonlinear terms on the dynamic response of the aircraft cannot be ignored. Therefore, for modeling the structure, the generalized nonlinear flexible Euler-Bernoulli beam model with bending-bending-torsion degrees of freedom and for modeling the aerodynamics, the Wagner function with the static stall model has been used. Using the developed model, the nonlinear behavior of the wing and the aircraft due to the occurrence of the BFF and wing flutter (WF) is studied. Also, a sensitivity analysis for the BFF is done and post-instability limit cycle oscillations and subcritical behaviors are investigated.

کلیدواژه‌ها [English]

  • full aircraft model
  • body-freedom flutter
  • generalized nonlinear Euler-Bernoulli beam model
  • Wagner aerodynamics
  • static stall model
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