بررسی آزمایشگاهی تأثیر سیستم تهویه انفرادی بر توزیع دما، سرعت و نارضایتی ناشی از کوران در یک محیط اداری

نوع مقاله : مقاله پژوهشی

نویسندگان

1 دانشگاه بیرجند، عضو هیات علمی گروه مهندسی مکانیک

2 دانشجوی دکتری، گروه مهندسی مکانیک، دانشگاه بیرجند

3 هیئت علمی. دانشگاه تربیت مدرس

چکیده

در این تحقیق سعی شده‌است تا به روش آزمایشگاهی، تأثیر وزش هوا در سیستم تهویه انفرادی به ازای دو دمای هوای ورودی (24 و 32 درجه سلسیوس) و دو حالت مختلف جانمایی دریچه ورودی (دریچه روی میز و دریچه زیر میز)، بر توزیع دما و سرعت در ناحیه حضور افراد و نیز احتمال وقوع نارضایتی موضعی کوران مورد ارزیابی قرار گیرد. نتایج نشان داد که عمق نفوذ حرارت و مومنتوم در اثر دریچه­های ورودی با هم برابر نیست؛ به طوری که تأثیر دمای دریچه بر توزیع دمای اتاق تا فاصله حدود 60 سانتیمتری قابل توجه است. این در حالی است که تأثیر سرعت ورودی دریچه تا فاصله حدود 110 سانتیمتری محسوس می‌باشد. در نتیجه، احساس حرارتی افراد تا فاصله حدود یک متری از دریچه، تحت تأثیر شرایط جریان ورودی قرارخواهدداشت. ضمن اینکه نتایج حاکی از آن است که نارضایتی ناشی از کوران در راستای افقی تا فاصله حدود 180 سانتی‌متری از دریچه محسوس است. همچنین بر اساس نتایج به‌دست‌آمده، سرعت و شدت اغتشاشات دو عامل اصلی در تعیین نارضایتی ناشی از کوران در سیستم تهویه انفرادی هستند و به دلیل اختلاط سریع و همدمایی هوای ورودی با هوای اتاق، دمای ورودی تأثیر قابل ملاحظه‌ای بر نارضایتی ناشی از کوران ندارد.

کلیدواژه‌ها

موضوعات

عنوان مقاله [English]

Experimental investigation of personalized ventilation effects on temperature, velocity, and draught discomfort distribution in an office

نویسندگان [English]

  • Alireza Zolfaghari 1
  • Peyman Ebrahimi Naghani 2
  • Mehdi Maerefat 3
1 University of Birjand
2 Department of Mechanical Engineering, University of Birjand, Iran
3 Department of Mechanical Engineering, Tarbiat Modares University
چکیده [English]

In this research, it has been tried to experimentally investigate the effect of a personalized ventilation system on airflow and temperature distribution in a room for two inlet air temperatures (24 and 32°C) and two different arrangements of the inlet diffusers (desk-mounted and under-desk air terminals). The results showed that the penetration depth of heat and momentum due to the inlet diffusers were not the same; So that the effect of inlet diffusers’ temperature on the room temperature distribution is significant up to a distance of about 60 cm. However, the effect of inlet velocity is noticeable up to a distance of about 110 cm. Therefore, the occupants’ thermal sensations up to the distance of about one meter from the inlet diffusers will be affected by the inlet conditions. Also, the results indicated that the draught discomfort along with the diffusers’ centerline is significant to a distance of about 180 cm. Based on the results, the air velocity and turbulence intensity are the two main factors in determining the draught discomfort in the personalized ventilation system and due to the rapid thermal mixing of inlet air with the room air, the effect of inlet temperature on the draught discomfort is not significant.

کلیدواژه‌ها [English]

  • Personalized ventilation system
  • Experimental study
  • Flow pattern
  • Draught discomfort

مراجع

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نشریه مهندسی مکانیک امیرکبیر
دوره 53، شماره 7
مهر 1400
صفحه 4397-4410

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