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Buoyancy Convection in a Square Cavity with Parallel Heaters Under Magnetic Field

  • Alireza Arab Solghar
Research Paper
  • 64 Downloads

Abstract

Buoyancy-driven convection in a square cavity induced by heated thin plates with arbitrary length is studied numerically. The hydrodynamics and thermal behavior of the flow are examined numerically using the two-phase mixture model and the finite volume method. Comparisons with previously published numerical works on natural convection in a cavity show excellent agreements between the results. For a given Rayleigh number and Hartman number, the effects of hot fins on the hydrodynamics and thermal parameters are presented and discussed. The steady-state results are depicted in terms of streamline and isotherm plots. It is found that the resulting convection pattern is stronger for the isothermal boundary condition. A better overall heat transfer can be achieved by placing horizontal heaters in symmetric configuration.

Keywords

Natural convection Nanofluid Heater CFD 

List of symbols

B0

Magnetic flux density

Cp

Specific heat (J/kg K)

g

Gravitational acceleration (m/s2)

h

Heat transfer coefficient (W/m2 K)

H

Enclosure height (m)

Ha

Hartman number

Lh

Dimensionless partition height

k

Thermal conductivity (W/m K)

Nu

Nusselt number

p

Pressure (N/m2)

P

Dimensionless pressure

Pr

Prandtl number

q

Heat flux per unit area (W/m2)

Ra

Rayleigh number

T

Temperature (K)

u, v

Velocity components (m/s)

U, V

Dimensionless velocity components

x, y

Cartesian coordinates (m)

X, Y

Dimensionless Cartesian coordinates

Greek symbols

α

Thermal diffusivity (m2/s)

β

Thermal expansion coefficient (K−1)

θ

Dimensionless temperature

μ

Dynamic viscosity (kg/m s)

ν

Kinematic viscosity (m2/s)

ρ

Density (kg/m3)

σ

Electrical conductivity

φ

Volume fraction of the nanoparticles

ψ

Stream function

Subscripts

c

Cold (lower value)

f

Fluid

h

Hot (higher value)

m

Average

nf

Nanofluid

p

Particle

References

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Copyright information

© Shiraz University 2017

Authors and Affiliations

  1. 1.Department of Mechanical EngineeringVali-e-Asr UniversityRafsanjanIran

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