Convective heat transfer enhancement of the Water-based magnetite nanofluids in the presence of a 3-D low-intensity magnetic field

نویسندگان

  • E. Esmaeili Birjand University of Technology, Department of Chemical Engineering, P.O. Box 97175/569, Birjand, Iran.
  • R. Ghazanfari Birjand University of Technology, Department of Mechanical Engineering, P.O. Box 97175/569, Birjand, Iran.
  • S. Farsad Birjand University of Technology, Department of Mechanical Engineering, P.O. Box 97175/569, Birjand, Iran.
چکیده مقاله:

In the current investigation, Fe3O4 water-based nanofluids were synthesized to examine the effect of an alternative 3-D external magnetic field on its thermal behavioral pattern. A solvothermal method was used to prepare the magnetite nanoparticles. To characterize the nanoparticles, the study employed transmission electron microscopy, X-ray diffraction, Fourier transform infrared spectroscopy, vibrating sample magnetometer and zeta-potential experiments. Vibrating sample magnetometer evaluations thoroughly confirmed the super-paramagnetic characteristics of the nanoparticles. Therefore, exposition of the resulting nanofluids to an AC external magnetic field led to the formation of aligned dipoles parallel to the applied field. Afterwards, the net magnetization in the absence of the external field was set to zero. Thermal measurements demonstrated an enhancement of convective heat transfer coefficients, particularly in the case of more diluted samples. The highest value of h was associated with the most diluted sample, where the h value was two times greater than that in the base fluid at V=1.4 V. This was attributed to the augmentation of both the Brownian motions and the viscosity gradients in the centerline of the test section.

برای دانلود باید عضویت طلایی داشته باشید

برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

منابع مشابه

convective heat transfer enhancement of the water-based magnetite nanofluids in the presence of a 3-d low-intensity magnetic field

in the current investigation, fe3o4 water-based nanofluids were synthesized to examine the effect of an alternative 3-d external magnetic field on its thermal behavioral pattern. a solvothermal method was used to prepare the magnetite nanoparticles. to characterize the nanoparticles, the study employed transmission electron microscopy, x-ray diffraction, fourier transform infrared spectroscopy,...

متن کامل

Study of Chemically Reactive Flow and Heat Transfer in the Presence of a Uniform Magnetic Field

The effects of chemical reaction, thermal stratification, Soret and Dufour numbers on magneto-hydrodynamic free convective heat and mass transfer of a viscous, incompressible,and electrically conducting fluid on a vertical stretching surface embedded in a saturated porous medium are presented. A similarity transform is used to reduce the governing partial differential equations into a syste...

متن کامل

Nanofluids for Heat Transfer Enhancement – A Review

A nanofluid is a dilute liquid suspension of particles with at least one critical dimension smaller than ~100 nm. Research works so far suggest that nanofluids offer excellent heat transfer enhancement over conventional base fluids. The enhancement depends on several factors such as particle shape, particle size distribution, volume fraction of nanoparticles, temperature, pH, and thermal conduc...

متن کامل

Measurement of Local Convective Heat Transfer Coefficient of Alumina-Water Nanofluids in a Double Tube Heat Exchanger

Heat transfer coefficient and thermal efficiency of γ-Al2O3/water nanofluids flowing through a double tube heat exchanger were experimentally investigated. The nanoparticles were well dispersed in distilled water at 0.05–0.15 %vol. A large number of experiments were performed at different fluid flow rates under turbulent flow regime (18,000<Re<40,000) and various nanofluid...

متن کامل

منابع من

با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید

ذخیره در منابع من قبلا به منابع من ذحیره شده

{@ msg_add @}


عنوان ژورنال

دوره 6  شماره 2

صفحات  141- 151

تاریخ انتشار 2015-04-01

با دنبال کردن یک ژورنال هنگامی که شماره جدید این ژورنال منتشر می شود به شما از طریق ایمیل اطلاع داده می شود.

میزبانی شده توسط پلتفرم ابری doprax.com

copyright © 2015-2023