بررسی عددی تأثیر ابعاد پنجره و زاویه وزش باد بر جریان داخل و خارج ساختمان

نوع مقاله : مقاله پژوهشی

نویسندگان

1 گروه مهندسی مکانیک، دانشگاه کاشان، کاشان، ایران

2 گروه مهندسی مکانیک، دانشگاه تفرش، تفرش، ایران

چکیده

بررسی جریان داخل و خارج ساختمان ناشی از جریان هوا در اطراف و داخل ساختمان یکی از راهکارهای مؤثر در بهره‌مندی بیشتر از پتانسیل تهویه طبیعی می‌باشد. یکی از پارامترهای مؤثر بر این جریان‎ها، ابعاد ورودی و خروجی‌‌های واقع بر دیواره‌‌های ساختمان می‌باشد. در این پژوهش با استفاده از معادلات ناویر-استوکس میان‌گیری شده در حالت دائمی و سه بعدی به همراه مدل توربولانسی انتقال تنش برشی، به مطالعه تأثیر این پارامتر مهم پرداخته شده است. بدین منظور از مدل‌هایی با سطح مقطع ورودی یکسان و نرخ تناسب مختلف استفاده شده است. بیشترین و کمترین میزان نرخ دبی حجمی هوای ورودی به ساختمان به ترتیب در مدل‌های با نرخ تناسب 1/56 و 0/39 مشاهده شده است. به منظور ارزیابی تأثیر زاویه وزش باد، زاویه‌های وزش 0 تا 75 درجه بررسی گردیده است. تحلیل نتایج نشان می‌دهد، این نرخ در زاویه‌‌های وزش بیش از 30 درجه، مستقل از ابعاد مقطع ورودی هوا به ساختمان است. با افزایش ارتفاع پنجره‌‌ها، از گستره نواحی سرعت بالا در نواحی داخلی ساختمان کاسته شده و بر نواحی سکون و با سرعت پایین افزوده می‌شود. تحلیل ضریب فشار در ناحیه خارج از ساختمان نشان می‌دهد در دیواره رو به باد تغییرات فشار بیشتر از دیواره پشت به باد می‌باشد.

کلیدواژه‌ها

موضوعات

عنوان مقاله [English]

CFD Simulation Investigation for Flow of Inside and Outside of Building: Impact of the Window Dimensions and the Wind Directions

نویسندگان [English]

  • Ahmad Shaker 1
  • Esmaeil Ebrahimi Fordoei 2
1 PHD Student of Mechanical Engineering at Kashan University
2 Associate professor of Mechanical Engineering at Tafresh University
چکیده [English]

Studying airflow inside and outside a building is crucial for optimizing natural ventilation. A key factor influencing these flows is the size of the inlet and outlet openings on the building’s walls. This study investigates the effect of this parameter using RANS equations in steady-state, three-dimensional conditions, with the SST-kω turbulence model. Models with identical cross-sectional areas at the building's inlet but different aspect ratios were used. The highest and lowest air flow rates into the building were observed in models with aspect ratios of 1.56 and 0.39, respectively. To examine the impact of wind direction on air flow rate, wind angles from 0 to 75 degrees were analyzed. Results show that air flow rate becomes independent of inlet dimensions at wind angles greater than 30 degrees. Additionally, increasing window height leads to a decrease in high-velocity regions inside the building, while low-velocity and stagnation areas expand. Pressure coefficient analysis on the building's exterior reveals that pressure variations on the windward wall are greater than on the leeward wall. This study highlights the importance of opening dimensions and wind direction in determining airflow behavior, providing valuable insights for enhancing natural ventilation strategies.

کلیدواژه‌ها [English]

  • Numerical Study
  • Opening Dimension
  • Ventilation Rate
  • Aspect Ratio
  • Wind Angel

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نشریه مهندسی مکانیک امیرکبیر
دوره 56، شماره 9
1403
صفحه 1249-1274

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