ارزیابی راهکارهای موثر در کاهش جزیره حرارتی مراکز شهری با تاکید بر سطوح سرد و سطوح سبز (نمونه موردی: باز طراحی یک بلوک شهری در منطقه راه آهن شهر تهران)
محورهای موضوعی : معماری و شهرسازی
گلنوش پارسی
1
,
حسین مدی
2
,
مریم آزموده
3
1 - كارشناسي ارشد معماري و انرژي. دانشگاه بين المللي امام خميني، قزوين، ايران.
2 - عضو هيئت علمي گروه معماري دانشگاه بين المللي امام خميني، قزوين، ايران.
3 - عضو هيئت علمي گروه معماري دانشگاه بين المللي امام خميني، قزوين، ايران. *(مسوول مکاتبات)
کلید واژه: جزیره حرارتی, راهکارهای کاهشی جزیره حرارتی, محله راه آهن تهران, شبیه سازی انویمت.,
چکیده مقاله :
زمینه و هدف: آسایش حرارتی یکی از الزامات شهر‌ها است. با وجود این امروزه بسیاری از شهر‌ها شاهد کاهش آسایش حرارتی هستند که یکی از دلایل آن افزایش جزایر حرارتی به‌واسطه افزایش محیط مصنوع است. کلانشهر تهران نیز سال‌هاست که با جزیره حرارتی روبه‌رو است. به همین منظور هدف این پژوهش بازطراحی و ارائه الگو برای عناصر مصنوع سیمای کف، جداره و بام در محله راه‌آهن تهران و یافت ترکیبی موثر از عوامل کاهنده برای کاهش جزیره حرارتی است.
روش بررسی: این پژوهش، با روش تجربی و نمونه‌کاوی (محله مسکونی راه آهن تهران) در تاریخ بهمن 1399 هجری شمسی انجام شده است. روش گرد‌آوری داده‌ها، غیرمستقیم و مستقیم و روش تحلیل، شبیه سازی با نرم‌افزار انویمت است. ابتدا شرایط موجود بر اساس پارامتر‌هایی محیطی تحلیل و پس از آن سناریوهای کاهشی مجددا بر اساس همان پارامتر‌ها بررسی و مقایسه شده است.
یافته‌ها: به طور کلی مصالح معابر تاثیر بسیاری در افزایش دما دارند و تغییر آن‌ها به مصالح بازتابنده سبب کاهش چشم‌گیر دما می‌شود. همراهی مصالح بازتابنده معابر با بام بازتابنده و سبز نیز موثر است، اگرچه که استفاده از بام سبز به دلیل کاهش بیشتر دما و افزایش رطوبت تبخیری جایگزین بهتری محسوب می‌شود. اولویت استفاده از نمای سبز به ترتیب در جهات جنوبی، غربی، شمالی و شرقی است و استفاده از نمای سبز بدون همراهی سایر راهکار‌ها تاثیر کمتری دارد.
بحث و نتیجه‌گیری : استفاده توامان از مصالح بازتابنده معابر، بام سبز و افزودن نمای سبز می‌تواند الگو مناسبی برای کاهش اثرات جزایر حرارتی در محدوده مورد نظر و یا هر محله مشابه آن باشد.
Background and Objectives: thermal comfort is one of the requirements in the cities. However, lots of cities have thermal problems recently which has been caused due to heat islands. Tehran has also faced urban heat island in some urban centers. The main goal of this research is redesigning and introducing a model for the built environment such as roads, façade and roof materials and finding a synthesis of effective strategies to eliminate heat island in Tehran Raah-Ahan neighborhood.
Material and Methodology: This study has been done in February,2021. The method of this research is experimental based on an urban case study. Data collection has been done by direct and indirect observations and analysis has been done by Envi-met software. First, current situation was analyzed based on some environmental parameters and then each mitigation scenarios, based on the same parameters, has been analyzed.
Findings: roads material have a great effect on increasing the temperature and changing them with reflective materials reduces temperature meaningfully. The combination of reflective and green roof is also effective although green roof is a better alternative due to further lowering the temperature and increasing evaporative humidity. The priority of adding green wall to the facades is south, west, north and east direction. In addition, implementing green wall without other strategies has little effect on reducing temperature.
Discussion and conclusion: Implementing reflective roof, green roof and green wall together is a proper model for mitigating heat island effect in railway station neighborhood or any similar neighborhoods.
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