Experimental evaluation of forced convective heat transfer of Fe3O4 ferrofluid in a horizontal u-shaped tube under variable magnetic field effect based on Taguchi approach

Abstract In this study, non-Newtonian pseudoplastic fluid flow equations for 2-D steady, incompressible, the natural convective heat transfer are solved numerically by pseudo time derivative. The stability properties of natural convective heat transfer in an enclosed cavity region heated from below under magnetic field effect are investigated depending on the Rayleigh and Chandrasekhar numbers. Stability properties are studied, in particular, for the Rayleigh number from 104 to 106 and for the Chandrasekhar number 3, 5 and 10. As a result, when Rayleigh number is bigger than 106 and Chandrasekhar number is bigger than 10, the instability occurs in the flow domain. The results obtained for natural convective heat transfer problem are shown in the figures for Newtonian and pseudoplastic fluids. Finally, the local Nusselt number is evaluated along the bottom wall.

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Numerical investigation of magnetic nanofluid forced convective heat transfer in existence of variable magnetic field using two phase model

Journal of Molecular Liquids ◽

10.1016/j.molliq.2015.07.077 ◽

2015 ◽

Vol 212 ◽

pp. 117-126 ◽

Cited By ~ 168

Author(s):

M. Sheikholeslami ◽

M.M. Rashidi ◽

D.D. Ganji

Keyword(s):

Magnetic Field ◽

Heat Transfer ◽

Convective Heat Transfer ◽

Numerical Investigation ◽

Convective Heat ◽

Variable Magnetic Field ◽

Phase Model ◽

Two Phase ◽

Magnetic Nanofluid ◽

Forced Convective Heat Transfer

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Effect of Magnetic Field on the Forced Convective Heat Transfer of Water–Ethylene Glycol-Based Fe3O4 and Fe3O4–MWCNT Nanofluids

Applied Sciences ◽

10.3390/app11104683 ◽

2021 ◽

Vol 11 (10) ◽

pp. 4683

Author(s):

Areum Lee ◽

Chinnasamy Veerakumar ◽

Honghyun Cho

Keyword(s):

Magnetic Field ◽

Heat Transfer ◽

Heat Transfer Coefficient ◽

Field Strength ◽

Ethylene Glycol ◽

Convective Heat Transfer ◽

Convective Heat ◽

Hybrid Nanofluid ◽

Forced Convective Heat Transfer ◽

The Magnetic Field

This paper discusses the forced convective heat transfer characteristics of water–ethylene glycol (EG)-based Fe3O4 nanofluid and Fe3O4–MWCNT hybrid nanofluid under the effect of a magnetic field. The results indicated that the convective heat transfer coefficient of magnetic nanofluids increased with an increase in the strength of the magnetic field. When the magnetic field strength was varied from 0 to 750 G, the maximum convective heat transfer coefficients were observed for the 0.2 wt% Fe3O4 and 0.1 wt% Fe3O4–MWNCT nanofluids, and the improvements were approximately 2.78% and 3.23%, respectively. The average pressure drops for 0.2 wt% Fe3O4 and 0.2 wt% Fe3O4–MWNCT nanofluids increased by about 4.73% and 5.23%, respectively. Owing to the extensive aggregation of nanoparticles by the external magnetic field, the heat transfer coefficient of the 0.1 wt% Fe3O4–MWNCT hybrid nanofluid was 5% higher than that of the 0.2 wt% Fe3O4 nanofluid. Therefore, the convective heat transfer can be enhanced by the dispersion stability of the nanoparticles and optimization of the magnetic field strength.

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