نوع مقاله : مقاله پژوهشی

نویسنده

عضو هیات علمی دانشگاه شهید رجایی

10.22061/jsaud.2021.6012.1597

چکیده

حیاط مرکزی در خانه های سنتی شهرهای کویری ایران، نقش بسیار مهمی در تلطیف و تعدیل هوای خانه دارد و به دلایل اقلیمی و فرهنگی، ترکیبات متفاوتی یافته است. حیاط مرکزی در خانه های اصفهان نیز ترکیب بخصوصی یافته و در دوره های مختلف متحول شده است. هدف اصلی این مقاله بررسی الگوی جریان هوای داخل حیاطهای مرکزی خانه های اصفهان (جامعه آماری پژوهش)، تحت تاثیر تغییرات کالبدی اواخر دوره قاجاریه در حیاط، بدلیل سبکهای وارداتی، بوده و خانه لباف بعنوان یک نمونه موردی تصادفی انتخاب شده است. تحقیق حاضر، ماهیتی میان رشته ای دارد و از یک روش ترکیبی جهت انجام پژوهش استفاده شده است. در مرحلة اول (پس از انتخاب خانه لباف بعنوان نمونه موردی) با استفاده از یک راهبرد تجربی، متغیرهای مستقل تأثیرگذار، شناسایی و متغیر وابسته (سرعت و جهت جریان هوای داخل) توسط دستگاه‌های دیجیتال و انجام آزمایش دود اندازه‌گیری شد. سپس داده‌ها با استفاده از راهبرد شبیه‌سازی، تحلیل شدند. شبیه‌سازی ها در این پژوهش با روش دینامیک سیال محاسباتی (CFD) و با استفاده از نرم افزارهای Gambit و Fluent صورت پذیرفت. نتایج نشان دادند که جریان هوای داخل حیاط مرکزی، در تراز ساکنین (زیر 2 متر)، برخلاف جهت باد خارج است و در میانه حیاط، یک جریان گردابه ای نامنظم بوجود می آید (موقعیت حوض) و پخش هوا به تمام نقاط خانه، از این نقطه انجام میشود. ضمن اینکه نیمه شمالی حیاط جریان هوای مطلوب تری نسبت به نیمه جنوبی دارد. همچنین بزرگتر شدن ابعاد حیاطهای قاجاری نسبت به صفوی، موجب افت کیفیت تهویه طبیعی آنها شده است. درخاتمه نیز پیشنهاداتی ارائه شده است.

چکیده تصویری

بررسی تغییرات کالبدی حیاط های مرکزی بر الگوی جریان هوای داخل آنها در خانه های دوران قاجار اصفهان با روش CFD (مورد پژوهی: خانه لباف)

کلیدواژه‌ها

موضوعات

عنوان مقاله [English]

Investigation of air flow pattern in the central courtyard in Qajar houses of Isfahan by CFD method

نویسنده [English]

  • O. R.

SRTTU

چکیده [English]

Traditional house yards in the desert cities of Iran play an important role in balancing and subtilizing the house's air. Its overall composition varies somewhat across Iran due to climatic and cultural reasons. Esfahan central courtyard houses also have a special combination. The main purpose of this paper is to investigate the process of central courtyard airflow (natural ventilation), influenced by the prevailing wind in late Qajar period houses in Isfahan (statistical population of research) and Labaf House as a random sample. The present study is an interdisciplinary research and uses a mixed method to conduct the research. In the first step (after selecting Labaf's house as a case study), using an empirical strategy, the independent variables were identified, and the dependent variables (velocity and direction of airflow) were measured by digital devices and smoke tests. The data were then analyzed using a simulation strategy. The simulations were performed by computational fluid dynamics (CFD) using Gambit and Fluent software. The results showed that in the statistical field the indoor air flow in the observer plane is opposite to the outside wind direction and in the northern third position (in the south north axis of the yard), an irregular eddy flow occurs and air is propagated to all locations of house, from this point.

کلیدواژه‌ها [English]

  • indoor airflow
  • natural ventilation
  • central courtyard
  • CFD method
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