الفهرس 
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Abstract
A tube bank is a form of heat exchanger, a device that is designed to allow fluids or gases to heat or cool, depending on the need. Tube banks are use in a wide variety of locations and its design is very popular around the world. Several manufacturers produce tube banks for different applications. It is also possible to design and install a custom device for an exact setting or application with special requirements.
The present study introduces computational fluid dynamics (CFD) simulation techniques as embedded in the commercially available CFD code (FLUENT -ANSYS). The CFD modeling techniques solve the continuity, momentum and energy conservation equations. The present study considers steady, two-dimensional, laminar, incompressible flow over both staggered and in-line circular tube bundles and over staggered flat tube used in heat exchanger applications.
In case of in-line and staggered tube banks the effects of different independent parameters, such as Reynolds number (Re), transverse pitch ratios (ST/D) and longitudinal pitch ratios (SL/D) on the pressure DROP across the banks and the average Nusselt number are studied in this work. In addition to, for staggered flat tube bank the effects of different independent parameters, as Reynolds number (Re), height ratio (H/D), length ratio (L/D) on the average Nusselt number are also studied.
In case of inline circular tube bank, arrangements with 25 domains are studied with ST/D, SL/D ranged from 1.25 to 3 and 25≤ Re ≤ 500.The results shows that there is a great effect on Nusselt number comes from increasing Reynolds number but not from the geometrical parameter SL/D and ST/D. The longitudinal pitch ratio (SL/D) has a small effect on the friction factor. There is an enhancement on the heat transfer ranged from 2.11 to 13.52 when SL/D changed from 1.25 to 3 at ST/D=3 and 25≤ Re ≤ 500.
For staggered circular tube bank, arrangements with 25 domains are studied with ST/D, SL/D ranged from 1.25 to 3 and 25≤ Re ≤ 500.The results show that, the Reynolds number has a great influence on the heat transfer for all studied ranges of longitudinal and transverse pitch ratios. However, by increasing Reynolds number the friction factor decreases for all longitudinal pitch ratios. There is an enhancement on the heat transfer ranged from 2.12 to 14.25when SL/D changed from 1.25 to 3 at ST/D=1.25 and 25≤ Re ≤ 500.
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Finally, for staggered flat tube bank, arrangements with 19 domains are studied with Dt =2, 2.5, 3, H/D = 1.5, 2, 4, L/D =4, 6, 7, 8 and 25≤ Re ≤ 500.The results indicates that, as the length ratio decreases the heat transfer increases. Also, the flat tube diameter should be small in order to obtain the highest heat transfer.