بررسی تاثیر مکان دریچه ورودی سیستم تهویه بر رفتار ریزگردها داخل اتاق با استفاده از روش شبکه بولتزمن چند زمانه

نوع مقاله : مقاله پژوهشی

نویسندگان

1 عضو هیات علمی، گروه مهندسی مکانیک، دانشگاه بجنورد

2 دانشگاه بجنورد

3 دانشگاه کلارکسون

چکیده

در این مقاله از روش عددی شبکه بولتزمن بر پایه مدل زمان آرامش چند گانه برای بررسی تاثیر مکان دریچه ورودی هوا بر رفتار ریزگردها داخل ساختمان استفاده شده است. هندسه مورد بررسی در این مقاله اتاقی با نسبت 1/0 یک اتاق واقعی با ابعاد 914/0×457/0×305/0 متر انتخاب شده و دو موقعیت مختلف (سقف و کف) برای دریچه ورودی هوا با ابعاد 101/0×101/0 متر در نظر گرفته شده است. از آنجاییکه جریان داخل اتاق مغشوش است از مدل حل ادی‌های بزرگ همراه مدل استاندارد اسماگورنسکی استفاده شده است.  همچنین ذرات با ابعاد 1 و 10 میکرومتر برای بررسی نحوه انتشار و ته نشینی بر روی دیواره‌های اتاق انتخاب گردیده است. تعداد ذرات ته نشین شده و همچنین خارج شده از اتاق برای ذرات با اندازه های مختلف نشان داد، هنگامی که دریچه در کف اتاق قرار دارد خروجی ذرات با سایز بزرگ (10 میکرومتر) نسبت به حالتی که دریچه در سقف قرار دارد بیشتر است و از لحاظ کیفیت، هوای داخل اتاق مناسب‌تر خواهد بود. اما برای ذرات با سایز کوچک (1 میکرومتر) تفاوت چندانی در خروجی ذرات مشاهده نشد. نتایج نشان داد که نیروی گرانش تاثیر زیادی در ته نشینی ذرات روی کف اتاق دارد به طوری که برای حالت دریچه ورودی هوا در سقف، میزان ته نشینی ذرات با اندازه 10 میکرومتر بر روی کف بسیار بیشتر (حدود 100 برابر) از ذرات با اندازه کوچک (1 میکرومتر) است.

کلیدواژه‌ها

موضوعات


عنوان مقاله [English]

Investigation of the Effect of Ventilation System Inlet Location on Particle Motion in a Room Using Multi Relaxation Time-Lattice Boltzmann Method

نویسندگان [English]

  • Hasan Sajjadi 1
  • Amin Amiri Delouei 2
  • Goodarz Ahmadi 3
1 Department of Mechanical Engineering, University of Bojnord
2 Department of Mechanical Engineering
3 Clarkson University
چکیده [English]

In this work multi-relaxation time lattice Boltzmann method is used to investigate the effect of the inlet air location on particle motion in a room. The scaled modeled room is one-tenth scale of a full-size room with dimensions of 0.914 m × 0.305 m × 0.457 m.  For an inlet air with dimension of 0.101 m×0.101 m, two locations (ceiling and floor) are studied.  The large Eddy simulation with the standard Smagorinsky model is utilized to simulate the turbulent indoor airflow. Particles with 1 and 10 micrometer sizes are selected for investigation of particle dispersion and deposition in the room. The simulation results for number of deposited particles and those exiting the room show that when the inlet air is on the floor, the number of larger 10 µm particles leaving through the exhaust register is more than the case for inlet on the ceiling. For smaller 1 µm particles, however, no significant difference between the floor and ceiling inlet air for particles leaving the room thought the exhaust register was seen.  The present results also show that the gravity significantly affects the particle deposition, and the number of deposited 10 µm particles on the floor are about 100 times that of the deposited 1 µm particles when the inlet air is at ceiling.

کلیدواژه‌ها [English]

  • Lattice Boltzmann method
  • Multi relaxation time
  • Particle deposition and dispersion
  • Large Eddy simulation
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