نوع مقاله: مقاله پژوهشی

نویسندگان

1 دانشکده مهندسی شیمی، نفت و گاز، دانشگاه سمنان، صندوق پستی: 19111-35131 ، سمنان - ایران

2 شرکت فن‌آوری‌های پیشرفته ایران، سازمان انرژی اتمی ایران، صندوق پستی: 55431-14399، تهران - ایران

3 پژوهشکده چرخه سوخت هسته‌ای، پژوهشگاه علوم و فنون هسته‌ای، سازمان انرژی اتمی ایران، صندوق پستی: 8486-11365، تهران ـ ایران

چکیده

معادله بولتزمن معادله‌­ای بسیار مهم در علم فیزیک و دینامیک سیالات است که برخورد­های دوتایی بین مولکول‌­ها را توصیف می­‌کند. یکی از روش­‌های حل معادله بولتزمن، روش شبیه‌­سازی مستقیم مونت­کارلو می‌­باشد. از آن‌­جا که فشار اغلب تجهیزات واحد­های فرایند غنی‌­سازی کم‌­تر از فشار اتمسفر است، ممکن است در طی عملیات غنی­‌سازی رطوبت هوا به دفعات و در مکان­‌های مختلف زنجیره­‌ها به لوله سیال نشت کرده و طی واکنش با گاز هگزافلوراید اورانیم سبب تولید رسوب بر روی سطوح داخلی روتور سانتریفیوژ و گاز هیدروژن فلوراید ­گردد. در این پژوهش تأثیر غلظت و فشار کل داخل روتور سانتریفیوژ فرضی برای شرایط دو جزیی (97/0=6ZUF و 03/0=ZHF)، (93/0=6ZUF و 07/0=ZHF)، (9/0=6ZUF و 1/0=ZHF)، (85/0=6ZUF و 15/0=ZHF) و سه جزیی (9/0=6ZUF، 05/0=ZHF و 05/0=ZAir) و (8/0=6ZUF، 1/0=ZHF و 1/0=ZAir) مورد بررسی قرار گرفته است. نتایج با روش تحلیلی مورد مقایسه قرار گرفته است. نتایج نشان داد که افزایش میزان گاز سبک به همراه گاز 6UF باعث کاهش شار جرمی محوری می‌­گردد.

کلیدواژه‌ها

عنوان مقاله [English]

Investigation of hydrodynamic parameters inside a gas centrifuge rotor in the presence of hydrogen fluoride and air light gases using DSMC and Boltzmann distribution function

نویسندگان [English]

  • M. Khajenoori 1 2
  • A. Haghighi Asl 1
  • J. Safdari 2 3
  • A. Norouzi 2

1 Faculty of Chemical, Gas and Petroleum Engineering, Semnan University, P.O.Box:35131-19111, Semnan - Iran

2 Faculty of Chemical, Gas and Petroleum Engineering, Semnan University, P.O.Box:35131-19111, Semnan - Iran

3 Advanced Technology Company of Iran, AEOI, P.O.Box:14399-55431, Tehran - Iran

چکیده [English]

The Boltzmann equation which describes binary collisions between molecules is a very important equation in physics and fluid dynamics. Direct Monte Carlo simulation is one of the methods to solve the Boltzmann equation. The moisture can leak to the fluid pipelines in the various places of cascades so many times through the enrichment operations since the pressure of the most enrichment process units is less than the atmospheric pressure. It causes the solid uranium precipitation on the inner surfaces of rotor and HF production upon the reaction with UF6. In the present work, the effect of concentration and total pressure inside a hypothetical centrifuge for binary component conditions (ZUF6=0.97, ZHF=0.03), (ZUF6=0.93, ZHF=0.07), (ZUF6=0.9, ZHF=0.1), (ZUF6=0.85, ZHF=0.15), and three component conditions (ZUF6=0.9, ZHF=0.05, ZAir=0.05) and (ZUF6=0.8, ZHF=0.1, ZAir=0.1) have been investigated. The results have been compared with those of the Boltzmann distribution function. Moreover, increment in the amount of light gas along with UF6 results in the decrement of ρνz.

کلیدواژه‌ها [English]

  • Boltzmann equation
  • Hydrogen fluoride
  • Gas Centrifuge
  • DSMC

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