eng
University of Sistan and Baluchestan,
Iranian Society Of Mechanical Engineers
Transport Phenomena in Nano and Micro Scales
2322-3634
2322-3634
2016-01-05
4
1
1
10
10.7508/tpnms.2016.01.001
2214
Conjugate Heat Transfer of MHD non-Darcy Mixed Convection Flow of a Nanofluid over a Vertical Slender Hollow Cylinder Embedded in Porous Media
B. Jafarian
1
M. Hajipour
2
R. Khademi
ramin.khademi85@gmail.com
3
Department of Chemical Engineering, Persian Gulf University, 75168, Boushehr, I. R.Iran
Faculty of Sciences, Science and Research Branch, Islamic Azad University, Tehran, I. R. Iran
Department of Chemical Engineering, University of Sistan and Baluchestan, 98164-161, Zahedan, I. R.Iran
In this paper, conjugate heat transfer of magneto hydrodynamic mixed convection of nanofluid about a vertical slender hollow cylinder embedded in a porous medium with high porosity have been numerically studied. The Forchheimer’s modification of Darcy’s law was used in representing the nanofluid motion inside the porous media. The governing boundary layer equations were transformed to non-dimensional differential equations by taking suitable similarity variables and solved numerically using differential quadrature method (DQM). The interfacial (solid-liquid) temperature distribution and the variations of velocity and temperature within boundary layer for different values of governing parameter in presence of uniform magnetic field have been presented and discussed. Our results demonstrate that heat transfer rate can enhance using nanofluid as well as porous medium, while magnetic field has no remarkable effect on the parameter. The computed results were also compared with those available in the existing literature and a good agreement was observed.
http://tpnms.usb.ac.ir/article_2214_beef3d1e5310e5883f92d7be578ea9ff.pdf
Conjugate heat transfer
differential quadrature method (DQM)
Magneto hydrodynamic (MHD)
MHD-mixed convection
Nanofluid
eng
University of Sistan and Baluchestan,
Iranian Society Of Mechanical Engineers
Transport Phenomena in Nano and Micro Scales
2322-3634
2322-3634
2016-01-05
4
1
11
18
10.7508/tpnms.2016.01.002
2215
Numerical Study of Single Phase/Two-Phase Models for Nanofluid Forced Convection and Pressure Drop in a Turbulence Pipe Flow
M. Esfandiary
1
A. Habibzadeh
amin.habibzadeh@yahoo.com
2
H. Sayehvand
3
Department of Mechanical Engineering, University of Bu Ali Sina, Hamedan, I. R.Iran
Department of Mechanical Engineering, Miandoab Branch, Islamic Azad University, Miandoab, I. R. Iran
Department of Mechanical Engineering, University of Bu Ali Sina, Hamedan, I. R.Iran
In this paper, the problem of turbulent forced convection flow of water- alumina nanofluid in a uniformly heated pipe has been thoroughly investigated. In numerical study, single and two-phase models have been used. In single-phase modeling of nanofluid, thermal and flow properties of nanofluid have been considered to be dependent on temperature and volume fraction. Effects of volume fraction and Reynolds number (3000
http://tpnms.usb.ac.ir/article_2215_7090436c2c4520b7deff9d521cb13a10.pdf
Heat transfer
Nanofluid
Single Phase/Two-Phase Models
Tube flow
Turbulent Forced convection
eng
University of Sistan and Baluchestan,
Iranian Society Of Mechanical Engineers
Transport Phenomena in Nano and Micro Scales
2322-3634
2322-3634
2016-01-05
4
1
19
28
10.7508/tpnms.2016.01.003
2216
The effect of various conductivity and viscosity models considering Brownian motion on nanofluids mixed convection flow and heat transfer
H. R. Ehteram
1
A. A. Abbasian Arani
2
G. A. Sheikhzadeh
sheikhz@kashanu.ac.ir
3
A. Aghaei
4
A. R. Malihi
alirezaaghaei21@gmail.com
5
Department of Mechanical Engineering, Mechanical Engineering University of Kashan, Kashan, I. R. Iran
Department of Mechanical Engineering, Mechanical Engineering University of Kashan, Kashan, I. R. Iran
Department of Mechanical Engineering, Mechanical Engineering University of Kashan, Kashan, I. R. Iran
Department of Mechanical Engineering, Mechanical Engineering University of Kashan, Kashan, I. R. Iran
Department of Mechanical Engineering, Mechanical Engineering University of Kashan, Kashan, I. R. Iran
In this paper the effect of using various models for conductivity and viscosity considering Brownian motion of nanoparticles is investigated. This study is numerically conducted inside a cavity full of Water-Al2O3 nanofluid at the case of mixed convection heat transfer. The effect of some parameters such as the nanoparticle volume fraction, Rayleigh, Richardson and Reynolds numbers has been examined. The governing equations with specified boundary conditions has been solved using finite volume method. A computer code has been prepared for this purpose. The results are presented in form of stream functions, isotherms, Nusselt number and the flow power with and without the Brownian motion taken into consideration. The results show that for all the applied models the stream functions and isotherm have approximately same patterns and no considerable difference has been observed. In all the studied models when considering the Brownian motion, the average Nusselt number is higher than not taking this effect into account. The models of Koo-Kleinstreuer and Li-Kleinstreuer give almost same values for the maximum stream function and average Nusselt number. It is also true about the models of Vajjha-Das and Xiao et al.
http://tpnms.usb.ac.ir/article_2216_acc4482d70d701a445174681a004e16b.pdf
Brownian motion
Mixed convection
Nanofluid
Numerical study
Variable properties
eng
University of Sistan and Baluchestan,
Iranian Society Of Mechanical Engineers
Transport Phenomena in Nano and Micro Scales
2322-3634
2322-3634
2016-01-05
4
1
29
35
10.7508/tpnms.2016.01.004
2217
A numerical investigation of γ-Al2O3-water nanofluids heat transfer and pressure drop in a shell and tube heat exchanger
P. Shahmohammadi
1
H. Beiki
hbeiki@qiet.ac.ir
2
Department of Chemical Engineering, Quchan University of Advanced Technology, 67335-94771, Quchan, I.R. Iran
Department of Chemical Engineering, Quchan University of Advanced Technology, 67335-94771, Quchan, I.R. Iran
The effect of γ-Al2O3 nanoparticles on heat transfer rate, baffle spacing and pressure drop in the shell side of small shell and tube heat exchangers was investigated numerically under turbulent regime. γ-Al2O3-water nanofluids and pure water were used in the shell side and the tube side of heat exchangers, respectively. Since the properties of γ-Al2O3-water nanofluids were variable, they were defined using the user define function. The results revealed that heat transfer and pressure drop were increased with mass flow rate as well as baffle numbers. Adding nanoparticles to the based fluid did not have a significant effect on pressure drop in the shell side. The best heat transfer performance of heat exchangers was for γ-Al2O3-water 1 vol.% and higher nanoparticles concentration was not suitable. The suitable baffle spacing was 43.4% of the shell diameter, showing a good agreement with Bell-Delaware method.
http://tpnms.usb.ac.ir/article_2217_fc03640ade649816fa27a7dc2ef54146.pdf
Baffle spacing
CFD models
γ-Al2O3-water nanofluids
Shell and tube heat exchanger
User define function (UDF)
eng
University of Sistan and Baluchestan,
Iranian Society Of Mechanical Engineers
Transport Phenomena in Nano and Micro Scales
2322-3634
2322-3634
2016-01-05
4
1
36
43
10.7508/tpnms.2016.01.005
2218
Lattice Boltzmann simulation of EGM and solid particle trajectory due to conjugate natural convection
J. Alinejad
alinejad_javad@iausari.ac.ir
1
J. A. Esfahani
2
Department of Mechanical Engineering, Sari Branch, Islamic Azad University, Sari, I. R. Iran
Department of Mechanical Engineering, Ferdowsi University of Mashhad, Mashhad 91775-1111, I. R. Iran
The purpose of this paper is to investigate the EGM method and the behavior of a solid particle suspended in a twodimensional rectangular cavity due to conjugate natural convection. A thermal lattice Boltzmann BGK model is implemented to simulate the two dimensional natural convection and the particle phase was modeled using the Lagrangian–Lagrangian approach where the solid particles are treated as points moving in the computational domain as a result of the fluid motion. Entropy generation due to heat transfer irreversibility, isotherms, streamlines and Nusselt numbers were obtained and discussed. Total entropy generations in various cases are also reported and optimum case is presented based on minimum entropy generation.
http://tpnms.usb.ac.ir/article_2218_409b21d322ba65244aea5bac67863989.pdf
Conjugate convection
Entropy generation
Lagrangian–Lagrangian (L–L)
Lattice Boltzmann model
particle trajectory
eng
University of Sistan and Baluchestan,
Iranian Society Of Mechanical Engineers
Transport Phenomena in Nano and Micro Scales
2322-3634
2322-3634
2016-01-05
4
1
44
51
10.7508/tpnms.2016.01.006
2219
MHD Boundary Layer Flow of a Nanofluid over an Exponentially Permeable Stretching Sheet with radiation and heat Source/Sink
N. Kishan
1
C. Kalyani
kpskalyani_1996@yahoo.com
2
M. Chenna Krishna Reddy
3
Department of Mathematics, Osmania University, Hyderabad Telangana, India
Department of Mathematics, R.B.V.R.R. women’s college, Hyderabad Telangana, India
Department of Mathematics, Osmania University, Hyderabad Telangana, India
The problem of steady Magnetohydrodynamic boundary layer flow of an electrically conducting nanofluid due to an exponentially permeable stretching sheet with heat source/sink in presence of thermal radiation is numerically investigated. The effect of transverse Brownian motion and thermophoresis on heat transfer and nano particle volume fraction considered. The governing partial differential equations of mass, momentum, energy and nanoparticle volume fraction equations are reduced to ordinary differential equations by using suitable similarity transformation. These equations are solved numerically using an implicit finite difference scheme, for some values of flow parameters such as Magnetic parameter (M), Wall mass transfer parameter(S), Prandtl number(Pr), Lewis number (Le), Thermophoresis parameter (Nt), Brownian motion parameter(Nb), Radiation parameter (R). The numerical values presented graphically and analized for velocity, temperature and nanoparticle volume fraction.
http://tpnms.usb.ac.ir/article_2219_af3d6715bca2686cfae0355e316dcd4a.pdf
Keller box
MHD
Nanofluid
Stretching permeable sheet
thermal radiation
eng
University of Sistan and Baluchestan,
Iranian Society Of Mechanical Engineers
Transport Phenomena in Nano and Micro Scales
2322-3634
2322-3634
2016-01-05
4
1
52
58
10.7508/tpnms.2016.01.007
2220
Investigation of two phase unsteady nanofluid flow and heat transfer between moving parallel plates in the presence of the magnetic field using GM
N. Hedayati
nima.hedayati883@gmail.com
1
A. Ramiar
2
Babol University of Technology, Department of Mechanical Engineering, Babol, I. R.Iran
Babol University of Technology, Department of Mechanical Engineering, Babol, I. R.Iran
In this paper, unsteady two phase simulation of nanofluid flow and heat transfer between moving parallel plates, in presence of the magnetic field is studied. The significant effects of thermophoresis and Brownian motion have been contained in the model of nanofluid flow. The three governing equations are solved simultaneously via Galerkin method. Comparison with other works indicates that this method is very applicable to solve these problems. The semi analytical analysis is accomplished for different governing parameters in the equations e.g. the squeeze number, Eckert number and Hartmann number. The results showed that skin friction coefficient value increases with increasing Hartmann number and squeeze number in a constant Reynolds number. Also, it is shown that the Nusselt number is an incrementing function of Hartmann number while Eckert number is a reducing function of squeeze number. This type of results can help the engineers to make better and researchers to investigate faster and easier.
http://tpnms.usb.ac.ir/article_2220_50ed5c7dbf662ee9f6258e90fa073876.pdf
Brownian
Galerkin method (GM)
Eckert number
Hartmann number
Nanofluid
Thermophoresis