بررسی اثر پدیدۀ کوران برروی فاکتورهای آسایش حرارتی در ساختمانی‌‌ با دیوار شیشه‌ای

نوع مقاله : مقاله پژوهشی

نویسندگان

1 گروه مهندسی مکانیک، دانشکده فنی و مهندسی، دانشگاه ولی عصر(عج) رفسنجان، ایران،

2 گروه مهندسی عمران، دانشکده فنی و مهندسی، دانشگاه ولی عصر(عج) رفسنجان، ایران،

چکیده

 استفاده از پنجره‌های بزرگ در ساختمان‌های مدرن یکی از طرح‌های محبوب در بین معماران و طراحان ساختمان است ولی افزایش مصرف انرژی در ساختمان به‌دلیل تشدید درفت ناشی از پنجره‌های بزرگ از جمله محدودیت‌ها در مقابل اجرای این طرح می‌باشد. هم‌چنین عدم امکان استفاده از سیستم‌های گرمایشی سنتی در محل پنجره‌ها از مشکلات دیگر فرا روی اجرای این طرح می‌باشد. در این مطالعه رویکرد استفاده از سیستم گرمایش جابه‌جایی اجباری با هدف کاهش اثرات کوران در قالب سه چیدمان مختلف از دمندۀ هوای گرم که دارای جانمایی الف) در زیر پنجره، ب) در دیوارهای جانبی و ج) به‌صورت ترکیبی در زیر و بالای پنجره قرار گرفته‌است بااستفاده از تکنیک دینامیک سیالات محاسباتی شبیه‌سازی شده‌است. بررسی نتایج بااستفاده از مقایسۀ توزیع دما و توزیع سرعت هوا برای هر سه چیدمان انجام شد و هم‌چنین آنالیز آسایش حرارتی بااستفاده از مدل فنگر برای هر سه حالت انجام گرفت. نتایج نشان دادند که حالت سوم با داشتن دمندۀ ترکیبی که در آن از دمنده‌هایی در پایین و بالای پنجره استفاده شده‌است دارای مطابقت قابل قبولی با استانداردهای آسایش حرارتی اشری و ایزو 7730 است، به‌طوری‌که در ارتفاع حساس مچ پا و ناحیۀ تنفسی در حالت نشسته و ایستاده، شاخص‌های مورد تحلیل در آسایش حرارتی در محدودۀ تعریف‌شدۀ استاندارد قرار گرفته‌است.

کلیدواژه‌ها

موضوعات


عنوان مقاله [English]

Investigation of Down-Draught Effect on The Thermal Comfort Indexes in The Building With Glazing Envelope

نویسندگان [English]

  • alireza arabsolghar 1
  • Nowrouz Heidari 1
  • Mohammad Shafiey dehaj 1
  • Afshin Iranmanesh 2
1 Department of Mechanical Engineering, Faculty of Engineering, Vali-e-Asr University of Rafsanjan, Iran
2 Department of Civil Engineering, Faculty of Engineering, Vali-e-Asr University of Rafsanjan, Iran
چکیده [English]

Employing large windows in the modern buildings is one the most popular approach among architects and buildings designers but the increase of energy consumption of the building due to down draught effects caused by large windows is one of the challenges against this type of design. Also, preventing of utilizing traditional heating system adjacent to the window is another concern of the approach. In this study, the use of forced convection heating system to mitigate the down-draught effects is simulated by computational fluid dynamic method for three different configurations of the warm air registers mounted (a) under the window; (b) alongside walls and (c) in mixed form under and above the window. The results were investigated by comparing air temperature and velocity distribution in the space and also the thermal comfort conditions were analyzed through Fenger model. The results showed that the third configuration of the inlet registers which they are installed beneath and above the window, is in satisfactory concord to ASHRAE standards and ISO 7730 such that at ankle and breathing height of sitting and standing position, the comfort condition indexes are in regular range of the standards.

کلیدواژه‌ها [English]

  • Thermal comfort
  • down-draught
  • glazing envelope
  • computational fluid dynamic
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