Effect of the Presence of Semi-circular Cylinders on Heat Transfer From Heat Sources Placed in Two Dimensional Channel
The effect of a semi-circular cylinders in a two dimensional channel on heat transfer by forced convection from two heat sources with a constant temperature has been studied numerically. Each channel contains two heat sources; one on the upper surface of the channel and the other on the lower surfac...
Main Authors: | , , |
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Format: | Article |
Language: | English |
Published: |
Tikrit University
2012-12-01
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Series: | Tikrit Journal of Engineering Sciences |
Online Access: | https://tj-es.com/ojs/index.php/tjes/article/view/479 |
Summary: | The effect of a semi-circular cylinders in a two dimensional channel on heat transfer by
forced convection from two heat sources with a constant temperature has been studied
numerically. Each channel contains two heat sources; one on the upper surface of the
channel and the other on the lower surface of the channel. There is semi-circular cylinder
under the source in upper surface and there is semi-circular cylinder above the source in
lower surface. The location of the second heat source with its semi-cylinder has been
changed and keeps the first source with its semi- cylinder at the same location. The flow
and temperature field are studied numerically with different values of Reynolds numbers
and for different spacing between the centers of the semi-cylinders. The laminar flow field
is analyzed numerically by solving the steady forms of the two-dimensional incompressible
Navier- Stokes and energy equations. The Cartesian velocity components and pressure on a
collocated (non-staggered) grid are used as dependent variables in the momentum
equations, which discretized by finite volume method, body fitted coordinates are used to
represent the complex channel geometry accurately, and grid generation technique based on
elliptic partial differential equations is employed. SIMPLE algorithm is used to adjust the
velocity field to satisfy the conservation of mass. The range of Reynolds number is (Re=
100 – 800) and the range of the spacing between the semi-cylinders is(1-4) and the Prandtl
number is 0.7.
The results showed that increasing the spacing between the semi-cylinders increases the
average of Nusselt number of the first heat source for all Reynolds numbers. As well as the
results show that the best case among the cases studied to enhance the heat transfer is when
the second heat source and its semi-cylinder located on at the distance (S=1.5) from the
first half of the cylinder and the Reynolds number is greater than (Re ≥ 400) because of the
separation behind of the first semi-cylinder where it works to reduce the area of section
flow, and this is leading to increase the speed and thus increases the rate of heat transfer. A
comparison of numerical results agrees well with published results.
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ISSN: | 1813-162X 2312-7589 |