مطالعه آزمایشگاهی تاثیر استفاده از سپرهای تشعشعی در کاهش انتقال حرارت جابجایی و تشعشعی در محفظه ای متشکل از دو استوانه هم‌محور متناهی در فشارهای مختلف

نوع مقاله: پژوهشی

نویسندگان

دانشگاه سمنان

چکیده

در مقاله حاضر، مطالعه آزمایشگاهی تاثیر قرارگیری سپرهای تشعشعی در محفظه‌ای متشکل از دو استوانه متناهی هم‌محور بر میزان تلفات حرارتی ناشی از جابجایی آزاد و انتقال حرارت تشعشعی مورد بررسی قرار گرفته است. محفظه مورد مطالعه شامل دو استوانه هم‌محور بوده که استوانه داخلی دارای دمای بالاتری می‌باشد و بین این دو استوانه از یک و یا دو سپر تشعشعی با جنس‌های مختلف (آلومینیوم، مس و استیل) در فواصل مختلف استفاده شده است. تاثیر خواص فیزیکی (ضریب جذب سپرهای تشعشعی)، فاصله سپرهای تشعشعی، دمای استوانه داخلی و فشار محفظه بر میزان تلفات حرارتی مورد بررسی قرار گرفته است. نتایج به دست آمده برای دماهای مختلف استوانه داخلی (200 و 400 درجه سانتیگراد) و فشارهای مختلف محفظه (2/0 و 0/1 اتمسفر) ارائه شده است، که نشان‌دهنده تاثیر مستقیم فشار محفظه و ضریب جذب سپر تشعشعی بر میزان تلفات حرارتی بین استوانه داخلی و خارجی می‌باشد.

کلیدواژه‌ها


عنوان مقاله [English]

Convection and Radiation Heat Loss Reduction between Two Finite Concentric Cylinders Using Radiation Shields at Different Pressure: Experimental Study

نویسندگان [English]

  • Seyfolah Saedodin
  • Mohammad Sadegh Motaghedi Barforoush
چکیده [English]

In the present work, the experimental Study of the radiation and natural convection heat losses from two finite concentric cylinders with radiation shields is investigated. The enclosure consists of two concentric cylinders with hotter inner cylinder and radiation shields with three different materials (aluminum, copper and steel) are inserted between the cylinders at different radial positions. The effects of physical properties (emissivity), geometrical effects of radiation shields, inner cylinder temperature, and enclosure pressure on the heat losses have been investigated. The calculations were performed for two different inner temperatures as 200, and 400ºC, and at two enclosure pressures of 0.2 and 1.0 atm. Results showed that the enclosure pressure and radiation shield emissivity together reduce the total heat loss from the inner cylinder.

کلیدواژه‌ها [English]

  • Free convection
  • radiation
  • Finite cylinders
  • Radiation shields
  • Enclosure
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