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ارزیابی تجربی تأثیر جهت جریان ورودی بر الگوی جریان و دما در اتاقی با سیستم توزیع هوای زیر سطحی | ||
| نشریه مهندسی مکانیک امیرکبیر | ||
| مقاله 18، دوره 53، شماره 5، مرداد 1400، صفحه 3057-3076 اصل مقاله (1.76 M) | ||
| نوع مقاله: مقاله پژوهشی | ||
| شناسه دیجیتال (DOI): 10.22060/mej.2019.16435.6365 | ||
| نویسندگان | ||
| سیدعلیرضا ذوالفقاری* 1؛ سعید تیموری2؛ مهدی افضلیان3؛ محمد رئیسی4؛ سیدمحمد هوشمند3 | ||
| 1دانشگاه بیرجند، عضو هیات علمی گروه مهندسی مکانیک | ||
| 2گروه مهندسی، دانشکده مهندسی، دانشگاه بیرجند، بیرجند، ایران | ||
| 3دانشجوی دکتری دانشگاه بیرجند | ||
| 4دانشجوی دکتری، دانشگاه بیرجند | ||
| چکیده | ||
| یکی از نگرانیها پیرامون عملکرد سیستم توزیع هوای زیر سطحی، امکان وقوع نارضایتی حرارتی موضعی مانند کوران و اختلاف عمودی دما است. در تحقیق حاضر، برای بررسی این نارضایتیها در این سیستم، دما، میانگین سرعت و شدت آشفتگی جریان برای دو حالت دریچه با تخلیه عمودی و افقی جریان برای دو دمای 16 و 20 درجه سلسیوس مورد ارزیابی قرار گرفته است. این پارامترها در فواصل صفر، 30 و 60 سانتیمتری از مرکز دریچه سیستم توزیع هوای زیر سطحی و در 8 ارتفاع مختلف از کف اندازهگیری شده است. همچنین، با استفاده از مدل آسایش حرارتی فنگر و استاندارد اشری، احساس حرارتی، درصد نارضایتی کلی افراد و درصد نارضایتی ناشی از کوران تعیین شده است. نتایج نشان میدهد میزان نارضایتی حرارتی افراد در اتاقی با سیستم توزیع هوای زیر سطحی به طور چشمگیری به جهت تخلیه جریان (افقی/عمودی) و میزان فاصله افراد از دریچه وابسته است. همچنین، نتایج حاکی از آن است که در صورت استفاده از دریچههای مناسب، میتوان ضمن حفظ شرایط آسایش افراد، دمای هوای ورودی را از 16 درجه سلسیوس به 20 درجه سلسیوس افزایش داد که این موضوع گام بزرگی در راستای کاهش مصرف انرژی به حساب میآید. | ||
| کلیدواژهها | ||
| سیستم توزیع هوای زیر سطحی؛ نارضایتی ناشی از کوران؛ نارضایتی ناشی از اختلاف عمودی دما؛ شدت آشفتگی جریان؛ تحقیق آزمایشگاهی | ||
| عنوان مقاله [English] | ||
| Experimental evaluation of the effect of supply air direction on air current and temperature in a room with underfloor air distribution system | ||
| نویسندگان [English] | ||
| Alireza Zolfaghari1؛ saeed teymori2؛ Mahdi Afzalian3؛ Mohammad Raesi4؛ Seyed Mohammad Hooshmand3 | ||
| 1University of Birjand | ||
| 2Department of Engineering, Faculty of Engineering, University of Birjand, Birjand, Iran | ||
| 3University of Birjand | ||
| 4University of Birjand | ||
| چکیده [English] | ||
| One of the concerns about the operation of underfloor air distribution systems is the occurrence of local thermal discomfort such as draught and vertical air temperature difference. In the present study, to investigate these discomfort parameters in a room with the mentioned system, the temperature, mean velocity and turbulence intensity for vertical and horizontal supply air diffuser with 16 and 20°C inlet temperatures were evaluated. These parameters were measured at 0, 30 and 60cm distances from the center of diffuser of the underfloor air distribution system at 8 different heights from the floor. Also, by using the Fanger model, thermal sensation, percentage of thermal discomfort and the percentage of thermal discomfort caused by the draught were determined. The results indicated that the amount of thermal discomfort in a room with an underfloor air distribution system is significantly dependent on supply air direction (horizontal/vertical) and, distance from the inlet diffusers. Also, the results showed that by using proper diffusers, while subjects’ thermal comfort maintains constant, the supply air temperature can be increased from 16 to 20 °C, which is a major step towards reducing energy consumption. | ||
| کلیدواژهها [English] | ||
| Underfloor air distribution system, Draught discomfort, Vertical air temperature difference discomfort, Turbulence intensity, Experimental evaluation | ||
| مراجع | ||
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