Anomalously increased effective thermal conductivities of ethylene glycol-based nanofluids containing copper nanoparticles

Eastman, J. A.; Choi, Seok Jin; Li, S.; Yu, William W.; Thompson, L. J.

doi:10.1063/1.1341218

Cited by 3,527 publications

(1,633 citation statements)

References 12 publications

Supporting

Mentioning

1,464

Contrasting

Unclassified

Order By: Relevance

“…Nanoparticles which include aluminium, copper, silver and titanium metals with/without their oxides are of great scientific interest as they are effectively a bridge between bulk materials and molecular structures. The thermal conductivity of the nanoparticles is high as compared to the conventional fluids, as verified in experimental studies conducted by Eastman et al [2] and Xuan and Lin [3] shown that with a small volumetric fraction of nanoparticles (typically less than 5%), the thermal conductivity of the base fluid is enhanced by 10-20%. Recently Selimefendigil and Oztop [4] reported that 14.11 % of averaged heat transfer enhancement is obtained when both cavities are filled with nanofluids at the highest value of nanoparticle volume fractions.…”

Section: Introductionmentioning

confidence: 59%

Numerical study of heat source/sink effects on dissipative magnetic nanofluid flow from a non-linear inclined stretching/shrinking sheet

Thumma¹,

Bég

Kadir

2017

Journal of Molecular Liquids

View full text Add to dashboard Cite

This paper numerically investigates radiative magnetohydrodynamic mixed convection boundary layer flow of nanofluids over a nonlinear inclined stretching/shrinking sheet in the presence of heat source/sink and viscous dissipation. The Rosseland approximation is adopted for thermal radiation effects and the Maxwell-Garnetts and Brinkman models are used for the effective thermal conductivity and dynamic viscosity of the nanofluids respectively. The governing coupled nonlinear momentum and thermal boundary layer equations are rendered into a system of ordinary differential equations via local similarity transformations with appropriate boundary conditions. The non-dimensional, nonlinear, well-posed boundary value problem is then solved with the Keller box implicit finite difference scheme. The emerging thermo-physical dimensionless parameters governing the flow are the magnetic field parameter, volume fraction parameter, power-law stretching parameter, Richardson number, suction/injection parameter, Eckert number and heat source/sink parameter. A detailed study of the influence of these parameters on velocity and temperature distributions is conducted. Additionally the evolution of skin friction coefficient and Nusselt number values with selected parameters is presented. Verification of numerical solutions is achieved via benchmarking with some limiting cases documented in previously reported results, and generally very good correlation is demonstrated. This investigation is relevant to fabrication of magnetic nanomaterials and high temperature treatment of magnetic nano-polymers.

show abstract

Section: Introductionmentioning

confidence: 59%

Numerical study of heat source/sink effects on dissipative magnetic nanofluid flow from a non-linear inclined stretching/shrinking sheet

Thumma¹,

Bég

Kadir

2017

Journal of Molecular Liquids

View full text Add to dashboard Cite

show abstract

“…The common nanoparticles that have been used are copper, aluminum, iron and titanium or their oxides. Experimental studies [2][3][4] show that even with the small volumetric fraction of nanoparticles (usually less than 5%), the thermal conductivity of the base liquid can be enhanced by 5 − 20%. The enhanced thermal conductivity of nanofluid together with the thermal conductivity of the regular liquid and turbulence induced by their motion contributes to a remarkable improvement in the convective heat transfer coefficient.…”

Section: Introductionmentioning

confidence: 99%

Nanofluid Flow over a Stretching Surface in Presence of Chemical Reaction and Thermal Radiation: An Application of Lie Group Transformation

Das¹,

Sarkar²,

Kumar³

2017

J. Sib. Fed. Univ., Math. phys.

View full text Add to dashboard Cite

This paper concerns with a steady MHD boundary layer flow of an electrically conducting nanofluid over a vertical permeable stretching surface with variable stream conditions. The transport model includes the effect of Brownian motion with thermophoresis in presence of chemical reaction and thermal radiation. The group theoretic method is used to find the symmetries of the governing partial differential equations. The reduced equations are solved numerically by employing a fourth order Runge-Kutta method and Shooting techniques to predict the heat and mass transfer characteristics of the nanofluid flow. Numerical results are presented through graphs and tables for several sets of values of the involved parameters of the problem and discussed in details from the physical point of view.

show abstract

“…Nanometer-sized stable metal, metal oxides or carbon particles in various forms could be suspended in the industrial heat transfer fluids (water and organic liquids), and can result in anomalously large enhancements of the thermal conductivities. [1][2][3][4][5] These reports show that only 5 vol. % of nanoparticles such as alumina (Al 2 O 3 ), copper oxide (CuO), and copper (Cu) dispersed in different base fluids, the thermal conductivity of the nanofluids was observed a significant improvement ($60%) as compared to the corresponding base fluids.…”

Section: Introductionmentioning

confidence: 99%

Near-Field Nanofluid Concentration Measurement by Rayleigh Particle Scattering Bragg Grating Evanescent Wave

2014

International Journal of Optomechatronics

View full text Add to dashboard Cite

We report an approach to detect near-field nanofluid concentration by scattering Bragg grating evanescent wave (EW). Since the suspended nanoparticles can enhance the scattering intensity of the EW from the thinned and tapered fiber with Bragg grating, the reflectance ratio of Bragg grating is dependent on the corresponding refractive index (RI) of the nanofluid at different nanoparticle volume fraction. A critical reflectance ratio measurement identifies the nanofluid concentration. Theory and simulation of scattering Bragg grating EW was analyzed. The scattering Bragg grating EW fiber sensing probe was designed and fabricated by the wet chemical etching method, and calibration was made by several chemical solutions without suspended nanoparticles. The example application of the nanofluid containing dispersed 40 nm SiO 2 nanoparticles demonstrates the feasibility. The reflectance ratio decreases by over 3.2% with the nanofluid concentration increasing from 0.25 wt.% to 4 wt.%, while the temperature disturbance can be negligible.

show abstract

Anomalously increased effective thermal conductivities of ethylene glycol-based nanofluids containing copper nanoparticles

Cited by 3,527 publications

References 12 publications

Numerical study of heat source/sink effects on dissipative magnetic nanofluid flow from a non-linear inclined stretching/shrinking sheet

Numerical study of heat source/sink effects on dissipative magnetic nanofluid flow from a non-linear inclined stretching/shrinking sheet

Nanofluid Flow over a Stretching Surface in Presence of Chemical Reaction and Thermal Radiation: An Application of Lie Group Transformation

Near-Field Nanofluid Concentration Measurement by Rayleigh Particle Scattering Bragg Grating Evanescent Wave

Contact Info

Product

Resources

About