شبیه‌سازی عددی و بهینه سازی انتقال حرارت نانوساختار مغناطیسی در یک کانال در حضور یک میدان مغناطیسی غیریکنواخت

نوع مقاله: مقالة‌ تحقیقی‌ (پژوهشی‌)

نویسندگان

1 عضو هیات علمی دانشگاه صنعتی سهند، دانشکده مهندسی مکانیک

2 دانشکده مکانیک، دانشکده فنی، دانشگاه خوارزمی، تهران، ایران

3 دانشکده مکانیک دانشگاه تهران

چکیده

در مقاله حاضر، تأثیر یک منبع میدان خارجی غیریکنواخت بر انتقال حرارت جابجایی اجباری نانوسیال مگنتیت (فروسیال) داخل کانالی با سطح گرم، به‌صورت عددی مورد مطالعه قرار گرفته است. هدف اصلی تأکید بر اهمیت موقعیت میدان مغناطیسی و بررسی احتمال افزایش انتقال حرارت از طریق یافتن مکان بهینه منبع میدان مغناطیسی است. مشاهده شد که میدان مغناطیسی گردابه‌هایی ایجاد کرده و بر ضخامت لایه مرزی حرارتی و تغییرات عدد ناسلت تاثیر می­گذارد. نتایج نشان می دهد تاثیر موقعیت میدان مغناطیسی وابسته به نوع شرط مرزی حرارتی است. همچنین نشان داده شده است که می­توان میدان دما و جریان سیال را با چند منبع میدان مغناطیسی کنترل نمود. با استفاده از الگوریتم ژنتیک، چیدمانی بهینه برای هشت منبع میدان مغناطیسی بدست آمده است که در مقایسه با حالت بدون میدان، منجر به 27% افزایش انتقال حرارت می­گردد.

کلیدواژه‌ها


عنوان مقاله [English]

Numerical Simulation and Optimization of Forced Convection Heat Transfer of Magnetic Nanofluid in a Channel in the Presence of a Non-Uniform Magnetic Field

نویسندگان [English]

  • Mohmmad Goharkhah 1
  • Mostafa Esmaeili 2
  • Mehdi Ashjaee 3
1 Sahand university
2 Department of Mechanical Engineering, Faculty of Engineering, Kharazmi University, Tehran, Iran.
3 Department of Mechanical Engineering, Faculty of Engineering, University of Tehran, Tehran, Iran
چکیده [English]

In this paper, the effect of an external non-uniform magnetic field on forced convective heat transfer of magnetite nanofluid (ferrofluid) in a heated channel is studied numerically. The main goal is to emphasize the importance of magnetic field location and investigate the possibility of heat transfer enhancement by finding the optimum location of magnetic field source.It is observed that the magnetic field results in creation of recirculation zones which affect the thermal boundary layer thickness and Nusselt number. Results show that the effect of magnetic field location on the heat transfer is completely dependent on the thermal boundary condition. It is also shown that the flow and temperature fields can be manipulated by application of multiple magnetic field sources. Using genetic algorithm (GA), an optimum arrangement for locations of eight magnetic field sources is obtainedresulting in a27% heat transfer enhancement compared to the case of no magnetic field.

کلیدواژه‌ها [English]

  • heat transfer
  • Forced Convection
  • ferrofluid
  • Mini channel
  • Magnetic field
  • optimization
  • Genetic Algorithm

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