نوع مقاله : مقالة‌ تحقیقی‌ (پژوهشی‌)

نویسندگان

1 استادیار، دانشکده مهندسی مکانیک، دانشگاه صنعتی سهند، تبریز، ایران

2 دانشکده مهندسی مکانیک، دانشگاه صنعتی سهند، تبریز، ایران

چکیده

در این مطالعه عددی، تاثیر میدان مغناطیسی بر انتقال حرارت جابجایی آزاد سیال مغناطیسی داخل یک محفظه، در شرایط میکروجاذبه، مورد بررسی قرار گرفته است. دو حالت، قرارگیری یک منبع میدان مغناطیسی زیر محفظه و دو منبع میدان در بالا و پایین محفظه بطور مجزا در نظر گرفته شده و شبیه-سازی‌ها برای شدت میدانها و فواصل مختلف منبع های میدان از محفظه انجام شده است. نتایج نشان می‌دهد به علت عدم تشکیل گردابه جریان در شرایط میکروجاذبه نرخ انتقال حرارت بسیار کمتر از حالت طبیعی است. با اعمال میدان مغناطیسی، گردابه القایی توسط نیروی حجمی، انتقال حرارت جابجایی در شرایط میکروجاذبه را افزایش می‌دهد. محاسبات نشان می‌دهد در حالت تک منبع، نرخ انتقال حرارت در حالت میکروجاذبه را تا 6.5 برابر می‌توان افزایش داد. همچنین قرار دادن دو منبع میدان مغناطیسی سبب افزایش قدرت گردابه داخل محفظه شده و در نتیجه موجب افزایش 19.7 برابری انتقال حرارت نسبت به حالت تک منبع می‌شود.

کلیدواژه‌ها

عنوان مقاله [English]

Magnetic field effects on heat transfer enhancement in an enclosure in microgravity conditions

نویسندگان [English]

  • Mohammad ghoharkhah 1
  • Behzad Alizadeh 2

1 Faculty of Mechanical Engineerign, Sahand University of Technology, Tabriz, Iran.

2 Faculty of mechanical engineering, Sahand university of technology, Tabriz, Iran

چکیده [English]

In this numerical study, effect of magnetic field on the convective heat transfer of a magnetic fluid in an enclosure is investigated in the microgravity condition. Two cases of a single magnetic field source under the enclosure and two sources on the top and below the enclosure are considered and the simulations are carried out for different magnetic field intensities and magnetic source distances from the enclosure. Results indicate that the heat transfer in the microgravity is much lower than that of natural condition due to the lack of the flow vortex. Applying the magnetic field and the induced vortex due to the magnetic body force cause a significant improvement of the heat transfer. Results show that the heat transfer rate in the microgravity condition can be increases up to 6.5 times. Moreover, placing two magnetic field sources improves the main vortex and leads to 19.7 times enhancement of the heat transfer rate compared to the case of single source.

کلیدواژه‌ها [English]

  • Convective heat transfer
  • Square enclosure
  • Magnetic fluid
  • Microgravity
  • Magnetic field
[1] Goharkhah, M.,  Esmaeili, M., and Ashjaee, M., “Numerical Simulation and Optimization ofForced Convection Heat Transfer of Magnetic Nanofluid in a Channel in thePresence of a Non-Uniform Magnetic Field,” Space science and technology, Vol. 11, No. 2, 2018, pp. 11-19
[2] Rosensweig, R.E., Ferrohydrodynamics: Courier Corporation, 2013.
[3] Ganguly, R., Sen, S. and Puri, I.K., “Thermomagnetic convection in a square enclosure using a line dipole,” Physics of Fluids, Vol. 16, No. 7, 2004, pp. 2228-2236.
[4] Sawada, T., et al., “Natural convection of a magnetic fluid in concentric horizontal annuli under nonuniform magnetic fields,” Experimental thermal and fluid science.,Vol. 7, No. 3, 1993, pp. 212-220.
[5] Krakov, M. and Nikiforov, I., “To the influence of uniform magnetic field on thermomagnetic convection in square cavity,” Magnetism and Magnetic Materials, Vol. 252, 2002, pp. 209-211.
[6] Ashouri, M., et al., “Correlation for Nusselt number in pure magnetic convection ferrofluid flow in a square cavity by a numerical investigation,” Magnetism and Magnetic Materials, Vol. 322, No. 22, 2010. pp. 3607-3613.
[7] Blums, E., Mezulis, A. and Kronkalns, G.  “Magnetoconvective heat transfer from a cylinder under the influence of a nonuniform magnetic field,” Physics: Condensed Matter, Vol. 20, No. 20, 2008, pp 204128.
[8] Banerjee, S., et al., “Effects of the Dipole Position on Thermomagnetic Convection in a Locally Heated Shallow Enclosure: Thermodynamic and Transport Analysis,” Numerical Heat Transfer, Part A: Applications, Vol. 57, No. 7, 2010, pp. 496-519.
[9] Wen, C. Y., Chen, C.-Y. and Yang, S.-F. “Flow visualization of natural convection of magnetic fluid in a rectangular Hele-Shaw cell,” Magnetism and Magnetic Materials, Vol. 252, 2002. pp. 206-208.
[10] Zablockis, D., Frishfelds, V. and Blums, E., “Numerical investigation of thermomagnetic convection in a heated cylinder under the magnetic field of a solenoid,” physics: condensed matter, Vol. 20, No. 20, 2008, pp. 204134.
[11] Tagawa, T., Shigemitsu, R. and Ozoe, H. “Magnetizing force modeled and numerically solved for natural convection of air in a cubic enclosure: effect of the direction of the magnetic field,” International journal of heat and mass transfer, Vol. 45, No. 2, 2002. pp. 267-277.
[12] Horsten, W. V.,  Odenbach, S.,   Stierstadt, K., “Magnetic benard convection under microgravity,” Advanced Space Research, Vol. 11, No. 7, 1991, pp. 251-254.
[13]Odenbach, S, “Microgravity experiments on thermomagnetic convection in magnetic fluid,” Magnetism and magnetic materials, Vol. 149, 1995, pp. 155-157.
[14] Zebib, A, “Thermal convection in a magnetic fluid,” Fluid Mechanics, Vol. 321, 1991, pp. I21- 136.
[15] Jasmine, H. A., “Rayleigh-Bénard Convection in Ferrofluids in the Microgravity Environment,” Scientific research, Vol. 8, No. 3, 2016., pp. 309-319.
[16] Hadavand, M. and Sousa, A. “Lattice boltzmann simulation of three‐dimensional thermomagnetic convection in a micro‐channel,” AIP Conference Proceedings. 2011. AIP.
[17] Morini, G.L., “Viscous heating in liquid flows in micro-channels,” International Journal of Heat and Mass Transfer, Vol. 48, No. 17, 2005. pp. 3637-3647.
[18] Kandelousi, M.S., “Effect of spatially variable magnetic field on ferrofluid flow and heat transfer considering constant heat flux boundary condition,” European Physical Journal Plus, Vol. 129, No. 11, 2014. pp. 248-257.
[19] Sheikholeslami, M. and Ganji, D.D., External magnetic field effects on hydrothermal treatment of nanofluid: numerical and analytical studies, William Andrew, 2016.