بررسی تجربی تاثیر موانع در افزایش راندمان حرارتی آبگرمکن مخزن‌دار گازسوز

نوع مقاله : مقاله پژوهشی

نویسندگان

1 گروه مهندسی مکانیک، دانشکده فنی مهندسی مکانیک، دانشگاه تبریز، تبریز، ایران.

2 تبریز*مهندسی مکانیک

3 دانشگاه تبریز، دانشکده مهندسی مکانیک

4 دانشیار/دانشگاه تبریز، دانشکده مهندسی مکانیک

چکیده

این تحقیق، افزایش راندمان حرارتی آبگرمکن مخزن‌دار گازسوز را به صورت تجربی بررسی می‌کند. برای این کار، از شش مانع جهت کاهش سرعت حرکت گازهای خروجی احتراق در تنوره آبگرمکن استفاده شد. با قراردادن 6 مانع در داخل تنوره، از خروج سریع گازهای حاصل از احتراق جلوگیری به عمل آمد.3 مانع از نظر هندسه و ابعاد تقریبا مانند هم و 3 مانع از نظر هندسه و ابعاد متفاوت هستند. همچنین، فاصله بین موانع یکسان در نظر گرفته شد. هندسه و ابعاد موانع از روی بررسی‌های تجربی انتخاب شدند. نتایج تجربی نشان دادند که در صورت استفاده از هندسه، ابعاد و ترتیب بهینه برای موانع، راندمان حرارتی تا 5/82 درصد افزایش می‌یابد. همچنین، نتایج اندازه‌گیری تحلیل‌گر گاز در آزمایشگاه، نشان داد که با بهبود راندمان حرارتی، گازهای آلاینده در خروجی دودکش نیز تقریبا در کمترین مقدار ممکن قرار داشتند. در نهایت، با درنظرگرفتن کمیت‌های تاثیرگذار بر روی عدم قطعیت راندمان حرارتی، با لحاظ سطح اطمینانی تقریباً برابر 95 درصد، عدم قطعیت کل برای راندمان حرارتی مدل بهینه نهایی عدد 17/0± محاسبه گردید.

کلیدواژه‌ها

موضوعات


عنوان مقاله [English]

Experimental study on the enhancement of the thermal efficiency of a household gas water heater

نویسندگان [English]

  • Shahram Kashaniasl 1
  • Mohammad Taghi Shervani Tabar 2
  • Mortaza Yari 3
  • Sima Baheri Islami 4
1 Department of Mechanical Engineering, University of Tabriz, Iran.
3 Department of Mechanical Engineering, University of Tabriz
4 Associate Professor/ Department of Mechanical Engineering, University of Tabriz
چکیده [English]

In this paper improvement of efficiency of a household gas water heater has been investigated experimentally. For this purpose, six baffles have been used for the deceleration of the hot exhaust gases in the middle tube of the water heater. Three of the baffles have almost the same geometry and dimension and the other three are different from geometry and dimension points of view. Also, the same distances between the baffles have been considered. The geometry and dimension of the baffles have been chosen by experimental tests. Experimental results show that by employing the optimum geometries and dimensions of the baffles and by selecting the optimum arrangement of the baffles, the thermal efficiency of the household gas water heater has been improved and increased up to 82.5%. Experimental results also show that by the improvement of the thermal efficiency of the household gas water heater, pollutant emissions which have been measured by the gas analyzers at the laboratory remained almost at the lowest level. Finally, by taking into account the effective parameters on the uncertainty for the thermal efficiency, in terms of the level of almost 95% for insurance against the reported number for the efficiency, the total uncertainty of the final optimized model for the thermal efficiency is ± 0.17.

کلیدواژه‌ها [English]

  • Household gas water heater
  • baffle
  • Thermal efficiency
  • Experimental test
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