بررسی اثرات مصالح دره خیابان شهری بر خرد اقلیم با استفاده از CFD در شیراز

نوع مقاله : مقاله پژوهشی (کاربردی)

نویسندگان

1 دانشجوی دکتری شهرسازی، دانشکده عمران، معماری و هنر، واحد علوم و تحقیقات، دانشگاه آزاد اسلامی، تهران، ایران.

2 استادیار، مدیر گروه شهرسازی، دانشکده معماری و شهرسازی، دانشگاه علم و صنعت ایران.

3 استادیار, دانشکده عمران، معماری و هنر، واحد علوم و تحقیقات، دانشگاه آزاد اسلامی، تهران، ایران.

4 دانشیار, دانشکده عمران، معماری و هنر، واحد علوم و تحقیقات، دانشگاه آزاد اسلامی، تهران، ایران.

10.48301/kssa.2023.354640.2225

چکیده

با افزایش شتابان روند شهرنشینی در شهر شیراز بررسی تأثیر مصالح در ساخت‌وسازهای عظیم سال‌های اخیر ضروری به نظر می‌رسد. هدف این پژوهش بررسی تأثیر ماهیت و نوع مصالح بر تغییرات روزانۀ متوسط دمای جداره‌های ساختمان و میانگین تابش با طول‌موج بلند جداره‌ها می‌باشد و بر این اساس سؤال مطرح‌شده -چگونگی تأثیر مصالح شهری بر تغییرات روزانۀ متوسط دمای جداره‌های ساختمان و میانگین تابش با طول‌موج بلند جداره‌ها - می‌باشد. در این تحقیق جریان هوا، انتقال حرارت و تابش خورشیدی در دره شهری با نسبت ابعاد یک در شیراز با نرم‌افزار فلوئنت شبیه‌سازی‌های عددی شد. از مدل‌های تلاطم k-ε برای مدل‌سازی اولیه و از مدل گردابه‌های بزرگ‌مقیاس در مدل‌سازی نهایی استفاده گردید. از سه نوع مصالح مختلف آلومینیوم، بتن خاکستری و سنگ سفید برای ساختمان‌ها و آسفالت برای کف زمین در شبیه‌سازی‌ها منظور گردید. یافته‌ها نشان داد که کم‌ترین میانگین دمای جداره‌ها، مربوط به سنگ سفید با دمای 294 درجه کلوین در حدود ساعت 5:00 صبح و بیشترین آن مربوط به مصالح آلومینیوم با دمای 337 درجه کلوین در حدود ساعت 14:00 بعدازظهر و کم‌ترین مقدار میانگین شار تابش خالص با طول‌موج بلند جداره‌ها مربوط به مصالح آلومینیوم به مقدار w/m2 53 در ساعت 6:30 صبح و بیش‌ترین مقدار آن مربوط به مصالح سنگ سفید در ساعت 15:00 به مقدار w/m2 295 است. در ضمن مقایسه‌ها نشان داد که گرداب‌های به وجود آمده در کنار ساختمان‌ها در هر سه نوع مصالح تقریباً دارای اندازۀ یکسانی می‌باشند؛ اما نکته جالب‌توجه وجود گرداب‌هایی به‌اندازۀ ارتفاع ساختمان در پشت ساختمان‌ها است.

کلیدواژه‌ها

موضوعات


عنوان مقاله [English]

Investigation of the Effect of Urban Street Canyon Materials on Microclimate by CFD in Shiraz

نویسندگان [English]

  • Shoeleh Shoara 1
  • Seyed Majid Mofidi Shemirani 2
  • Seyed Kamaleddin Shahriari 3
  • Zahra Sadat Saeideh Zarabadi 4
1 PhD Candidate, Faculty of Civil Engineering, Art and Architecture, Science and Research Branch, Islamic Azad University, Tehran, Iran.
2 Assistant Professor, Head of Urban Development Department, Iran University of Science and Technology, Tehran, Iran.
3 Assistant Professor, Faculty of Civil Engineering, Art and Architecture, Science and Research Branch, Islamic Azad University, Tehran, Iran
4 Associate Professor, Faculty of Civil Engineering, Art and Architecture, Science and Research Branch, Islamic Azad University, Tehran, Iran.
چکیده [English]

Given the rapid acceleration of urbanization in the city of Shiraz in recent years, it seems necessary to study the impact of new developments. The purpose of this study was to investigate the effects of urban canyon material on daily average temperature and net long-wave wall flux. Therefore, the question arises of how urban surface material affects average daily temperatures and wall long-wave net fluxes. In this study, ANSYS FLUENT software was used to numerically model airflow, heat transfer, and solar radiation in a three-dimensional urban environment. The k-ε turbulence model was implemented for the initial modeling, whereas the large-eddy simulation model was utilized for the final modeling. The simulation also used three different materials for the urban facade; aluminum, gray concrete, and white stone, and asphalt for the ground. It was observed that the lowest wall’s mean temperature was related to the white stone with a temperature of 294K at approximately 5:00 AM and the highest value was associated with the aluminum material with a temperature of 337K at approximately 14:00 PM. The lowest value of the average net long-wave radiation flux of walls equal to 53 w/m2 was related to the aluminum material at approximately 6:30 AM and the highest amount equivalent to 295 w/m2 was related to the white stone material at 15 PM. Comparisons revealed that the magnitude of the vortices generated next to the building was approximately the same for the three materials and the formation of vortices behind buildings that were as tall as the buildings.

کلیدواژه‌ها [English]

  • Local climate zone
  • Large eddy simulation
  • Ventilation
  • Urban canyon
  • Material
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