تحلیل روش‌های مختلف تولید آشفتگی ورودی در رهیافت شبیه‌سازی گردابه‌های بزرگ برای پیش‌بینی پراکندگی آلاینده‌ها در اطراف ساختمان‌های مدل

نویسندگان

دانشگاه علم و صنعت ایران

چکیده

هدف از این مطالعه بررسی و تحلیل عددی مکانیزم‌های مؤثر بر میدان جریان و پراکندگی آلاینده‌ها پیرامون یک دره خیابانی ساده و طویل توسط رهیافت شبیه‌سازی گردابه‌های بزرگ با استفاده از چندین روش مختلف تولید آشفتگی ورودی است. به‌همین منظور، از چهار روش گردابه، نگاشتی، سنتزی و بدون آشفتگی ورودی به‌عنوان تولید کننده‌های آشفتگی ورودی در رهیافت شبیه‌سازی گردابه‌های بزرگ استفاده شده است. نتایج حاکی از آن است که تمامی روش‌ها قادر به پیش‌بینی دو ساختار مهم گردابه دره و گردابه گوشه هستند که تأثیر زیادی بر تهویه هوای داخل دره خیابانی می‌گذارند. مقادیر غلظت برروی دیوار بادپناه ساختمان اول حدود 4 برابر دیوار بادگیر ساختمان دوم به‌دست آمده است. از بین روش‌های مختلف تولید آشفتگی ورودی، روش گردابه دقیق‌ترین روش و روش بدون آشفتگی ورودی، کم‌دقت‌ترین روش است.‏

کلیدواژه‌ها


عنوان مقاله [English]

Analysis of Various Inflow Turbulence Generation Methods in Large Eddy Simulation Approach for Prediction of Pollutant Dispersion around Model Buildings

نویسندگان [English]

  • F. Bazdidi Tehrani
  • D. Badaghi
  • M. Kiamansori
  • M. Jadidi
چکیده [English]

The purpose of the present study is to investigate and analyze numerically, the effective mechanisms on the flow field and pollutant dispersion around a simple and long street canyon by means of Large Eddy Simulation (LES) approach using various inflow turbulence generation methods. For this purpose, four methods i.e. vortex, mapping, synthetic and no-inlet perturbation methods are used as inflow turbulence generators in LES. Results suggest that all methods are capable of capturing the two important structures of canyon vortex and corner eddy, which have great influences on air ventilation inside the street canyon. The magnitudes of concentration on the leeward wall of the first building are approximately four times as much as those
of windward wall of the second building. Among the various inflow turbulence generation methods, the vortex method is the most precise method and no-inlet perturbation method is the least precise method.

کلیدواژه‌ها [English]

  • Pollutant dispersion
  • Large eddy simulation approach
  • Inflow turbulence generation methods
  • Street canyon
  • Computational fluid dynamics
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