بررسی چگالی نوترون در حالت زیربحرانی با چشمه‌ی تپی نوترون

نویسندگان

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

2 گروه فیزیک، دانشگاه صنعتی ارومیه، صندوق پستی: 16116-414، ارومیه ـ ایران

چکیده

در طول راه‌اندازی خنک، رآکتور در حالت زیربحرانی است، لذا نمی‌توان از چشمه‌ی نوترون خارجی صرف‌نظر کرد. در این مقاله یک حل تحلیلی در حضور چشمه‌ی نوترون تپی با یک گروه نوترون تأخیری در طول راه‌اندازی یک رآکتور آب تحت فشار با سوخت U235 ارایه شده است. حل تحلیلی براساس بسط چگالی نوترون در توان‌هایی از زمان تولید نوترون‌های آنی است. معادله‌های سینتیک نقطه‌ای با این روش برای واکنش‌پذیری‌های ثابت و خطی قابل حل است و به نتایج بهتری در مقایسه با کارهای تحلیلی دیگران می‌انجامند، ولی برای واکنش‌پذیری سینوسی، کارآمد نیست. بنابراین پاسخ چگالی نوترون به واکنش‌پذیری سینوسی به کمک بررسی نقاط ثابت و روش نمای لیاپانوف تحلیل شده است.
 

کلیدواژه‌ها


عنوان مقاله [English]

Neutron density study in sub-critical state with pulsed neutron source

نویسندگان [English]

  • Rasoul Khodabakhsh 1
  • Sohrab Behina 2
  • Masoud Seyedi 1
چکیده [English]

 During the cold start-up, the reactor is in sub-critical state. Therefore, the external neutron source cannot be neglected. In this research paper, the analytical solution of neutron point kinetics equations with a group of delayed neutrons in the presence of the pulsed neutron source in a pressurized-water reactor with 235U as a fuel is presented. The analytical solution is based on the expansion of the neutron density in powers of the prompt neutrons generation time. The point kinetics equations with this method are solvable for step and ramp reactivity and lead to better results compared with other analytical works, but are not solvable for sinusoidal reactivity. So, the neutron density response to sinusoidal reactivity is analyzed by using the fixed point and Lyapunov exponents method.
 

کلیدواژه‌ها [English]

  • Pulsed neutron source
  • Prompt neutrons generation time
  • Lyapunov exponent
  • Neutron density

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