مدلسازی آزمایشگاهی سیستم انتقال حرارت تیوب رادیولوژی با نانوسیال کربنی چند دیواره و بررسی بهبود ضریب انتقال حرارت

نویسندگان

دانشگاه علوم پزشکی کرمانشاه

چکیده

تیوب اشعه ایکس، اصلی ترین بخش هر دستگاه رادیولوژی در تولید اشعه ایکس به شمار می آید. یکی از مهمترین مشکلات این تجهیزات، حرارت تولیدی بسیار بالا در آند تیوب در نتیجه برخورد پرتوهای الکترونی پر انرژی بر سطح آن می باشد . نقص در انتقال مناسب این حرارت ، تخریب زودهنگام وکاهش عمر تیوب اشعه ایکس را موجب خواهد گردید. با توجه به نقش مهم روغن اطراف تیوب اشعه ایکس بعنوان انتقال دهنده گرمای تولیدی در آند ، در این مقاله، برای اولین بار در دنیا روغن مذکور با نانوسیال با درصدهای وزنی مختلف جایگزین و بهبود ضریب انتقال حرارت در شرایط گوناگون مورد بررسی قرار گرفته است. بدین صورت که مدل آزمایشگاهی سیستم حرارتی تیوب اشعه ایکس با استفاده از المنت حرارتی ساخته شده و گرمای مشابه با گرمای تولیدی در آند، با اعمال توان به المنت ایجاد گردید. نانوسیال مورد نیاز نیز از ترکیب نانولوله کربنی چند دیواره و روغن ترانسفورمر در درصدهای وزنی مختلف ساخته و رفتار حرارتی مدل تیوب با استفاده از روغن معمولی مورد استفاده در سیستم های فعلی رادیولوژی و نانوسیال ها مقایسه گردید. نتایج تجربی بدست آمده حاکی از آن است که استفاده از نانوسیال ، انتقال حرارت را به نحو چشمگیری بهبود بخشیده است. استفاده از این فنآوری نوین در سیستم های رادیولوژی و تجهیزات مشابه علاوه بر حذف فرآیند پیچیده ساخت تیوب مولد اشعه ایکس، کارآئی این نوع تجهیزات را بطور قابل ملاحظه ای افزایش خواهد داد.

کلیدواژه‌ها


عنوان مقاله [English]

Laboratory modeling of heat transfer system of radiology tube using multi-walled carbon nanofluid and evaluation of heat transfer coefficient

نویسندگان [English]

  • Behrouz Moradhasel
  • Vahab Dehlaghi
  • Mohammad Taghi Eivazi
  • Mostafa Taghipour
چکیده [English]

X-ray tube is the main part of the radiology device to produce X-ray. One of the main problems with this equipment is the too much heat generated at the anode of the tube as a result of clashing the high-energy electron beam on its surface. Lack of proper transfer of heat generated at the anode, further destruction and reduces the life time of the X-ray tube. Considering the important role of oil around the X-ray tube as a transferor of generating heat, in this article, this oil is replaced by different weight percentages of nanofluids and heat transfer coefficients have been investigated in different conditions for the first time in the world. However experimental models of X-ray tube heating system was built with heating element and the same amount of heat generated at the anode was produced by applying the electrical power to the element. In addition, the nanofluid has been built with the combination of multi-walled carbon nanotubes and transformer oil in different weight concentration and thermal behavior of the tube has been compared using conventional oil and nanofluids. The obtained experimental results indicate that using improves the heat transfer significantly. Using this new technology in radiology systems and similar equipment, in addition to eliminating the complicated process of X-ray tubes, the efficiency of this type of equipment will increase considerably.

کلیدواژه‌ها [English]

  • Heat transfer
  • Radiology tube
  • X-ray
  • Anode
  • Nanofluid
  • Transformer Oil
  • Weight concentration
  • Multi-Walled Carbon Nanotube
 
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