تفرق موج از یک استوانه قائم دایره‎ای به روش اجزای محدود مرزی مقیاس‎شده

نوع مقاله: کوتاه

نویسندگان

1 استادیار مرکز آموزش عالی فنی و مهندسی بوئین زهرا، قزوین

2 دانش آموخته کارشناسی ارشد مهندسی عمران - سازه های دریایی، دانشگاه هرمزگان

چکیده

روش اجزای محدود مرزی مقیاس‎ شده یک روش نیمه تحلیلی نسبتاً جدید است که از مزایای دو روش‎ اجزای محدود و المان مرزی برخوردار است. در روش اجزای محدود مرزی مقیاس ‎شده، با بکارگیری روش باقیمانده وزن‎ دار و اجزای محدود، معادله دیفرانسیل حاکم تنها روی مرز دامنه مسئله ضعیف و گسسته ‎سازی می‎شود سپس دستگاه معادلات حاصل‎ در راستای شعاعی به کمک روش تحلیلی حل می‎شود. در این مقاله، مسئله مقدار مرزی تفرق موج از یک استوانه قائم دایره‎ای با استفاده از روش اجزای محدود مرزی مقیاس ‎شده مورد بررسی قرار گرفته است. تنها مرز دایره ای استوانه با استفاده از المان‏های یک بُعدی در پیرامون دایره گسسته‎ سازی شده است. در اثر اعمال روش، معادله حاکم با مشتقات جزیی به یک دستگاه معادلات دیفرانسیل معمولی تبدیل شده است. پاسخ عددی دستگاه معادلات روی مرز جسم و در گره‌ها به کمک ترکیب خطی از پاسخ‌های تحلیلی که شرایط مرزی در دوردست را ارضا می‎کنند، بدست آمده است. مقایسه پارامترهای هیدرودینامیکی شامل پتانسیل سرعت کل، برآمدگی موج و مؤلفه افقی نیروی تحریک موج با نتایج روش تحلیلی و سایر روشهای عددی نشان دهنده دقت و بازدهی بالا در روش اجزای محدود مرزی مقیاس‏ شده است.

کلیدواژه‌ها

موضوعات


عنوان مقاله [English]

Water Wave Diffraction by a Vertical Circular Cylinder Using Scaled Boundary Finite Element Method

نویسندگان [English]

  • Keyvan Sadeghi 1
  • R Gohari 2
1 Technical University of Buein Zahra, Qazvin, Iran
2 University of Hormozgan, Bandar Abbas, Iran
چکیده [English]

The Scaled Boundary Finite Element Method (SBFEM) is a rather new semi-analytical method that combines the merits of finite element and boundary element methods. The SBFEM method uses weighted residual technique and finite elements to weaken and discretize the governing differential equation only on the boundary of the problem and then solves the resulted system of weakened ordinary differential equations in the radial direction, analytically. In this article, the boundary-value problem of water wave diffraction by a vertical circular cylinder has been solved by SBFEM method. Only the circular boundary is discretized with one-dimensional finite-elements. The governing partial differential equation is transformed to a system of ordinary differential equations, whose numerical solution on the nodes of circular boundary is obtained with the aid of analytical solutions that satisfy the far field boundary condition. The comparison of hydrodynamic parameters such as total velocity potential, wave elevation and horizontal component of wave excitation force with those obtained from analytical and other numerical methods shows high accuracy and efficiency of the present SBFEM method.

کلیدواژه‌ها [English]

  • Scaled Boundary Finite Element Method
  • Vertical Circular Cylinder
  • Water wave diffraction
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