نوع مقاله : مقاله فنی

نویسندگان

پژوهشکده‌ی راکتور و ایمنی هسته‌ای، پژوهشگاه علوم و فنون هسته‌ای، سازمان انرژی اتمی ایران، صندوق پستی: 1589-81465، اصفهان ـ ایران

چکیده

 ( با عرض پوزش به دلیل عدم امکان تایپ فرمول اصل چکیده را از روی پی دی اف مطالعه فرمایید)
در این تحقیق، امکان­سنجی استفاده از رآکتور MNSR اصفهان به عنوان چشمه نوترون حرارتی برای پرتونگاری نوترونی انجام شده است. برای تولید یک باریکه با شدت و کیفیت مناسب از آلومینیم با ضخامت 0.7 سانتی­متر به عنوان فیلتر نوترون سریع و از بیسموت و سرب به ضخامت 1 سانتی­متر به عنوان فیلتر گاما بهره برده شده است. نسبت L/D سامانه پرتونگاری نوترونی شبیه‌سازی شده 90 و زاویه واگرایی برابر 2.1 درجه می‌باشد. در این طراحی شار نوترون حرارتی در محل تصویربرداری .s2n/cm 05 E+47/1، شار نوترون­های حرارتی به دز گاما
/mR2 n/cm06E+96/2 و نسبت شار نوترون‌­های حرارتی به شار کل نوترون­‌ها 5/92% محاسبه شد. به کمک ساخت این سامانه پرتونگاری برای رآکتور MNSR می‌توان به بسیاری از کاربردهای عملی و علمی یک سامانه پرتونگاری با نوترون دست یافت.

کلیدواژه‌ها

عنوان مقاله [English]

Design calculation of a vertical thermal neutron beam for neutron radiography at Esfahan MNSR

نویسندگان [English]

  • J Khorsandi
  • A Asgari
  • P Kavyani
  • J Mokhtari

چکیده [English]

In this paper, the MCNPX code is applied for feasibility study of using the Isfahan MNSR as a neutron source for neutron radiography. To produce a good neutron beam in terms of intensity and quality, the aluminum (Al) with thickness of 0.7 cm, and bismuth (Bi) and lead (Pb) with thickness of 1 cm are used as the fast neutron filter, and the gamma filter, respectively. The L/D ratio of the designed neutron radiography facility is 90 and the diverging angle is 2.1degree. The thermal neutron flux, the ratio of thermal neutron to gamma dose rate, and the thermal neutron content at the beam exit plane are evaluated 1.47E+05 n/cm2.s,  2.96E+06 n/cm2.mR, and 92.5%, respectively. If such thermal neutron beam is built in Isfahan MNSR, many practical and scientific applications of the NR would be realized.

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