بررسی و مدل سازی تغییرات غلظت رادون در داخل یک اتاق نمونه

نوع مقاله : مقاله پژوهشی کامل

نویسندگان

1 گروه فیزیک، دانشکده علوم پایه، دانشگاه پیام نور، تهران، ایران

2 گروه فیزیک، دانشکده علوم پایه، دانشگاه حکیم سبزواری، سبزوار، ایران

10.22055/jrmbs.2020.16182

چکیده

در این پژوهش به منظور بررسی تغییرات غلظت رادون در محیطهای مسکونی، از یک اتاق بسته نمونه به مساحت 12 مترمربع استفاده گردید. در این اتاق گاز رادون از سطوح کف و دیوارها با آهنگ مختلفی منتشر و مسیر تهویه طبیعی هوا از زیر درب به سمت پنجره وجود داشت. با بهره‌گیری از یک دستگاه اندازه گیری رادون دقیق، غلظت رادون در نقاط مختلف اتاق و برای شرایط و زمانهای متفاوت اندازه‌گیری گردید و با نتایج شبیه‌سازی حاصل از بکارگیری روش دینامیک سیالات محاسباتی (CFD)، در شرایط و زمانهای متناظر مقایسه شد. همچنین به منظور اعتبار‌سنجی نتایج این دو روش، از داده های حاصل از روش حل تحلیلی استفاده گردید. این داده‌ها نشان می‌دهند که پس از یک تهویه طبیعی هوای بسیار آرام، غلظت رادون از یک توزیع یکنواخت نسبی با مقدار متوسط Bq/m3 81 به یک توزیع غیرهمگن نسبی در بازه Bq/m3 12 تا Bq/m3 44 کاهش می یابد. تطابق مناسب نتایج شبیه‌سازی شده و داده‌های تجربی با نتایج حاصل از حل تحلیلی، صحت مدلسازی انجام‌شده را مشخص می سازد.

کلیدواژه‌ها

موضوعات


عنوان مقاله [English]

Investigating and modeling radon density changes inside a sample room

نویسندگان [English]

  • Mohammad Zabihinpour 1
  • ali asghar Mowlavi 2
  • Behnam Azadegan 2
1 1Department of Physics, Faculty of Science, Payame Noor University, Tehran, Iran
2 2Department of Physics, Faculty of Science, Hakime Sabzevari University, Sabzevar, Iran
چکیده [English]

This study aims to investigate changes in radon concentrations in residuals areas, using a sample closed room with the surface area of 12 m2. In the room, radon gas emitted from the floor and walls surfaces with different emission rates, and gaps under the door and around the window were the natural ventilation routes. Radon concentrations were measured in different points of the room in different circumstances and times using an accurate radon detector and then compared with the simulation results from Computational Fluid Dynamics (CFD) technique under corresponding conditions and times. The analytical data were used to validate the results of these two techniques. The results indicate that the radon concentration decreases from a relatively uniform distribution of about 81 Bq/m3 to a relative non-uniform distribution in the range from 12 Bq/m3 to 44 Bq/m3 after a very slow natural ventilation. The simulation results demonstrate an appropriate agreement with the experimental data that indicate the accuracy of performed modeling.

کلیدواژه‌ها [English]

  • Radon
  • Exhalation rates
  • CFD method
  • natural ventilation
  • Concentration distribution
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