Suripeddi Srinivas^a , Akshay Gupta^b,*, Ashish Kumar Kandoi^b

Frontiers in Heat and Mass Transfer, Vol.5, pp. 1-12, 2014, DOI:10.5098/hmt.5.21

Abstract The present work deals with the flow and thermal analysis of nanofluid in the wavy channels. The governing flow equations are solved numerically using CFD package assuming single phase approach. To study the effect of the concentration and size variation of the nanoparticle, the concentration and size are varied from 0% - 5% and 25 nm - 100 nm respectively over the Reynolds number range of 250-1500 for Au-water nanofluid. The effect on heat transfer enhancement because of corrugation of wavy channel is analyzed on four different shapes (sinusoidal, triangular, trapezoidal and square) channels. The More >

Zan Wu^a, Zhaozan Feng^b, Bengt Sundén^a,*, Lars Wadsö^c

Frontiers in Heat and Mass Transfer, Vol.5, pp. 1-10, 2014, DOI:10.5098/hmt.5.18

Abstract Thermal conductivity and rheology behavior of two aqueous nanofluids, i.e., alumina and multi-walled carbon nanotube (MWCNT) nanofluids, were experimentally investigated and compared with previous analytical models. Information about the possible agglomeration size and interfacial thermal resistance in the nanofluids were obtained and partially validated. By incorporating the effects of interfacial thermal resistance, a revised model was found to accurately reproduce the experimental data based on the agglomeration size extracted from the rheology analysis. In addition, the thermal conductivity change of the alumina/water nanofluid with elapsed time was investigated. Thermal conductivity measurements were also conducted for More >

Lei Lu^1,2, Li-Hua Liu^3,4, Xiao-Xiao Li¹

CMES-Computer Modeling in Engineering & Sciences, Vol.101, No.1, pp. 1-15, 2014, DOI:10.3970/cmes.2014.101.001

Abstract In this paper, we use the modified decomposition method (MDM) to solve the unsteady flow of a nanofluid squeezing between two parallel equations. Copper as nanoparticle with water as its base fluid has considered. The effective thermal conductivity and viscosity of nanofluid are calculated by the Maxwell- Garnetts (MG) and Brinkman models, respectively. The effects of the squeeze number, the nanofluid volume fraction, Eckert number, δ on Nusselt number and the Prandtl number are investigated. The figures and tables clearly show high accuracy of the method to solve the unsteady flow. More >

Imen Mejri^1,2, Ahmed Mahmoudi¹, Mohamed Ammar Abbassi¹, Ahmed Omri¹

FDMP-Fluid Dynamics & Materials Processing, Vol.10, No.1, pp. 83-114, 2014, DOI:10.3970/fdmp.2014.010.083

Abstract This study examines natural convection in a square enclosure filled with a water-Al₂O₃ nanofluid and subjected to a magnetic field. The side walls of the cavity have spatially varying sinusoidal temperature distributions. The horizontal walls are adiabatic. A Lattice Boltzmann method (LBM) is applied to solve the governing equations for fluid velocity and temperature. The following parameters and related ranges are considered: Rayleigh number of the base fluid, from Ra=10³ to 10⁶, Hartmann number from Ha=0 to 90, phase deviation (γ =0, π/4, π/2, 3π/4 and π) and solid volume fraction of the nanoparticles between ø = 0 and More >

Jiwon Yu^a , Seok-Won Kang^a, Saeil Jeon^b, Debjyoti Banerjee^a,*

Frontiers in Heat and Mass Transfer, Vol.3, No.1, pp. 1-9, 2012, DOI:10.5098/hmt.v3.1.3004

Abstract Experiments were performed to study the forced convective heat transfer of de-ionized water (DI water) and aqueous nanofluids in a microchannel and temperature measurements were obtained using an array of nanosensors (i.e., thin film thermocouples or “TFT”). Heat flux values were calculated from the experimental measurements for temperature recorded by the TFT array. The experiments were performed for the different test fluids where the flow rate, mass concentration (of silica nanoparticles ~10-30 nm diameter) in the colloidal suspension and the wall temperature profile (as well as applied heat flux values) were varied parametrically.
Anomalous enhancement… More >

A. Rasekh^a,*, D.D. Ganji^b, S. Tavakoli^b

Frontiers in Heat and Mass Transfer, Vol.3, No.4, pp. 1-6, 2012, DOI:10.5098/hmt.v3.4.3003

Abstract The present paper deals with the analysis of boundary layer flow and heat transfer of a nanofluid over a stretching circular cylinder in the presence of non-uniform heat source/sink. The governing system of partial differential equations is converted to ordinary differential equations by using similarity transformations, which are then solved numerically using the Runge–Kutta–Fehlberg method with shooting technique. The solutions for the temperature and nanoparticle concentration distributions depend on six parameters, Prandtl number Pr, Lewis number Le, the Brownian motion parameter Nb, the thermophoresis parameter Nt, and non-uniform heat generation/absorption parameters A*, B*. Numerical results are presented both… More >

Massimo Corcione¹

FDMP-Fluid Dynamics & Materials Processing, Vol.7, No.2, pp. 175-200, 2011, DOI:10.3970/fdmp.2011.007.175

Abstract Free convection heat transfer in nanofluids from horizontal isothermal cylinders is investigated theoretically. The main idea upon which the present work is based is that nanofluids behave more like a single-phase fluid rather than like a conventional solid-liquid mixture. This assumption implies that all the convective heat transfer correlations available in the literature for single-phase flows can be extended to nanoparticle suspensions, provided that the thermophysical properties appearing in them are the nanofluid effective properties calculated at the reference temperature. In this connection, two empirical equations, based on a wide variety of experimental data reported… More >

R. J. Johnson^∗, R. Pitchumani^†

Frontiers in Heat and Mass Transfer, Vol.1, No.1, pp. 1-9, 2010, DOI:10.5098/hmt.v1.1.3007

Abstract Much research is currently being performed with carbon nanotube additives to neat resin systems to enhance properties such as thermal and electrical conductivity, strength, modulus and damping. Fabrication of parts based on carbon nanotube filled resin systems requires information on their cure kinetics and rheology, which has been relatively less studied so far. This work presents an extensive experimental study that systematically characterizes the cure kinetics and viscosity as a function of degree of cure and temperature of EPON 815C/EPICURE 3274 epoxy resin system laden with carbon nanotubes. Studies are conducted to determine the effects More >

A. Arefmanesh¹, M. Najafi², M. Nikfar³

CMES-Computer Modeling in Engineering & Sciences, Vol.69, No.2, pp. 91-118, 2010, DOI:10.3970/cmes.2010.069.091

Abstract Procuring a numerical solution through an application of the meshless local Petrov-Galerkin method (MLPG) on the fluid flow and mixed convection in a complex geometry cavity filled with a nanofluid is the scope of the present study. The cavity considered is a square enclosure having a lower temperature sliding lid at the top, a differentially higher temperature wavy wall at the bottom, and two thermally insulated walls on the sides. The nanofluid medium used is a water-based nanofluid, Al₂O₃-water with various volume fractions of its solid. To carry out the numerical simulations, the developed governing equations… More >

A. Podolny^1,2, A. Nepomnyashchy³, A. Oron⁴

FDMP-Fluid Dynamics & Materials Processing, Vol.6, No.1, pp. 13-40, 2010, DOI:10.3970/fdmp.2010.006.013

Abstract A general model for two-component transport phenomena applicable for both nanofluids and binary solutions is formulated. We investigate a combined long-wave Marangoni and Rayleigh instability of a quiescent state of a binary (nano-) liquid layer with a non-deformable free surface. The layer is heated from below or from above. The concentration gradient is induced due to the Soret effect. A typical behavior of monotonic and oscillatory instability boundaries is examined in the limit of asymptotically small Lewis numbers and poorly conducting boundaries in the two important long-wave domains k~Bi1/2and k~Bi1/4. More >