بررسی تاثیر پایه بر میدان جریان باد اطراف دو ساختمان‌ هم ردیف

نوع مقاله : مقاله پژوهشی

نویسندگان

گروه مهندسی مکانیک، واحد شیراز دانشگاه آزاد اسلامی، شیراز، ایران

چکیده

در تحقیق حاضر میدان جریان متلاطم باد اطراف دو ساختمان هم ردیف بدون پایه و بر روی پایه در فواصل مختلف به روش عددی بررسی شده است. به منظور مدل سازی آشفتگی از دو مدل آشفته( k-ɛ)دسته نرمالسازی مجدد و k-ɛتحقق پذیر استفاده شده است. براساس شبیه سازی‌های عددی صورت گرفته، توزیع سرعت طولی اطراف ساختمانهای منفرد بدون پایه و بر روی پایه با نتایج آزمایشگاهی مقایسه شده اند. سپس با استفاده از مدل اعتبار سنجی شده، برای شبیه سازی میدان جریان اطراف ساختمانهای هم ردیف بدون پایه و بر روی پایه از مدل k-ɛتحقق پذیر استفاده شده و سرعت طولی برای دو عدد رینولدز 17000 و 170000 ارائه شده اند. به صورت تقریبی میدان سرعت اطراف مدل ساختمان های بدون پایه در دو عدد رینولدز مشابه می‌باشند، اگر چه برای ساختمان های بر روی پایه تفاوت اندکی در توزیع سرعت به ویژه در بخش زیرین و روی ساختمانها مشاهده می‌شود. مقایسه نتایج نشان می‌دهد که قرار دادن ساختمان بر روی پایه به دلیل حذف جریان برگشتی در پشت ساختمان منجر به کاهش نیروی پسای وارده به ساختمان می‌گردد. همچنین وجود پایه ها سبب می‌شود که طول اتصال مجدد روی ساختمان بالادست افزایش یابد.

کلیدواژه‌ها

موضوعات


عنوان مقاله [English]

Effect of Support on Wind Flow Field Around Array of Two Inline Buildings

نویسندگان [English]

  • H. Haghighifard
  • M. Tavakol
Department of Mechanical Engineering, Shiraz Branch, Islamic Azad University, Shiraz, Iran
چکیده [English]

In the present study turbulent wind flow field around inline surface-mounted and supported buildings has been investigated numerically. In order to model turbulence, re-normalization group k‑ε and realizable k‑ε turbulence models are employed. According to the numerical simulations, stream-wise velocity profiles around single surface-mounted and supported buildings are compared with the experimental data. Consequently, the validated model with realizable k‑ε turbulence models is used to simulate flow field around two inline surface-mounted and supported buildings. Results have been reported for two Reynolds numbers (17000, 170000). Approximately, same velocity field was observed for non-supported buildings at two flow Reynolds numbers. Although, for supported buildings small difference is observed in the velocity profile under and above the building. Comparison of results for non-supported and supported buildings shows that behind the supported buildings the near ground reversed flow region was removed and lead to the lower drag force on such building. Moreover, supports increase the reattachment length on the upstream building.

کلیدواژه‌ها [English]

  • Inline buildings
  • supported building
  • separation length
  • reversed flow
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