شبیه‌سازی توزیع شار نوترون در یک رآکتور ناهمگن بحرانی استوانه‌ای با غنای سوخت مختلف به روش اجزای محدود

نوع مقاله: مقاله پژوهشی

نویسندگان

گروه فیزیک، دانشکده علوم، دانشگاه ارومیه، صندوق پستی: 165-57153، ارومیه ـ ایران

چکیده

روش اجزای محدود برای متغیرهای فضایی معادله­ی چند گروهی ترابرد نوترون­ در هندسه­ی استوانه­ای دوبعدی (r, z) به کار گرفته شده است.­ این معادله با استفاده از نواحی چهارگوش منظم در صفحه­ی (r, z) گسسته شده است. این روش گسسته­سازی با چندجمله­ای­های درون­یاب توان اول خطی و توان دوم مکعبی به عنوان توابع پایه، در برنامه­ی ANSYS به کار گرفته شده است. در این­جا به شارهای زاویه­ای اجازه داده شده است تا در مرزهای نواحی، گسسته باشند. نتا‍‍‍‍‍‍‍­یج به دست آمده نشان می­دهد که شار نوترون­ها در ناحیه­ی سطح بیرونی قلب رآکتور ناهمگن افزایش یافته است. در نتیجه فاصله­ی مرکز تا سطح بیرونی با شار نوترونی ثابت در مقایسه با یک رآکتور با غنای ثابت میله­های سوخت افزایش می­یابد. افزایش ناحیه با شار نوترونی ثابت نه تنها منجر به افزایش قدرت رآکتور با شکل و حجم هندسی یکسان می­شود بلکه از نظر مهندسی مواد (قلب رآکتور)، محدودیت­ها را کاهش می­دهد.

کلیدواژه‌ها


عنوان مقاله [English]

Simulation of Neutron Flux Distribution in a Cylindrical Critical Heterogeneous Reactor with Different Fuel Concentrations, Using Finite Element Method (FEM)

نویسندگان [English]

  • R Khoda-Bakhsh
  • S Behnia
  • A Jafari
چکیده [English]

The finite element method is applied to the spatial variables of multi-group neutron transport equation in a two-dimensional cylindrical (r, z) geometry. The equation is discretized using rectangular sub regions in the (r, z) plane. The discontinuous method with the bilinear or biquadratic Lagrang's interpolating polynomials and basis functions is used in the ANSYS program. Here, the angular fluxes are allowed to be discontinued across the sub region boundaries. Some numerical calculations have been made on a real cylindrical Aristotle reactor with different fuel concentrations on the fuel rods; the results indicate that the flux and power of the heterogeneous critical reactor increase on the edges of the core in comparison with the homogeneous one.
 

کلیدواژه‌ها [English]

  • Finite element method
  • Fuel Concentration
  • Cylindrical Reactor
  • Heterogeneous Reactor
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