Heat transfer analysis of short helical borehole heat exchangers

Since 2006, The Center for Innovation and Applied Technology (CIAT) at Cooper Union for the Advancement of Science and Art has been developing a system to use thermal pollution to heat the growth medium of green roofs. CIAT is researching various apparatus and techniques, including shell-and-tube and shell-and-coil heat exchangers, to improve its heated ground agricultural projects. There are limited recorded observations on shell-and-coil heat exchangers; therefore a laboratory work station was created of interchangeable components to test the efficiency of a variety of coil designs. This paper discusses the data collected on temperature, pressure, and flow rates for a straight tube and two different helical coils. The analysis of this data indicates the superiority of a helical coil design when compared to a straight tube design with respect to both rating and heat transfer rate. The same data analysis has lead to preliminary observations on how the contour properties of a helical coil influence the heat transfer rate through a coil. The authors intend to further this helical coil research to develop a useful mathematical model for determining efficient designs for shell-and-coil heat exchangers.

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Borehole Heat Exchangers: heat transfer simulation in the presence of a groundwater flow

Journal of Physics Conference Series ◽

10.1088/1742-6596/501/1/012033 ◽

2014 ◽

Vol 501 ◽

pp. 012033 ◽

Cited By ~ 5

Author(s):

A Angelotti ◽

L Alberti ◽

I La Licata ◽

M Antelmi

Keyword(s):

Heat Transfer ◽

Groundwater Flow ◽

Heat Exchangers ◽

Heat Transfer Simulation ◽

Borehole Heat Exchangers

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Simplified heat transfer analysis method for large-scale boreholes ground heat exchangers

Energy and Buildings ◽

10.1016/j.enbuild.2016.02.001 ◽

2016 ◽

Vol 116 ◽

pp. 593-601 ◽

Cited By ~ 8

Author(s):

Yu Mingzhi ◽

Ma Tengteng ◽

Zhang Kai ◽

Cui Ping ◽

Hu Aijuan ◽

...

Keyword(s):

Heat Transfer ◽

Heat Exchangers ◽

Large Scale ◽

Heat Transfer Analysis ◽

Analysis Method ◽

Ground Heat Exchangers

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Performance of One- and Two-Row Tube and Plate Fin Heat Exchangers

Journal of Heat Transfer ◽

10.1115/1.3246726 ◽

1984 ◽

Vol 106 (3) ◽

pp. 627-632 ◽

Cited By ~ 42

Author(s):

E. C. Rosman ◽

P. Carajilescov ◽

F. E. M. Saboya

Keyword(s):

Heat Transfer ◽

Mass Transfer ◽

Heat Exchangers ◽

Local Heat Transfer ◽

Heat Transfer Analysis ◽

Transfer Coefficients ◽

Mass Transfer Coefficients ◽

Fin Efficiency ◽

Heat Transfer Coefficients ◽

Experimental Apparatus

Heat exchangers consisting of finned tubes are commonly employed in air conditioning systems, air heaters, radiators, etc. Local measurements of mass transfer coefficients on fins, obtained by Saboya and Sparrow, are very nonuniform. In the present work, an experimental apparatus was set up to measure overall heat transfer coefficients for two-row tube and plate fin heat exchangers. The obtained results, together with Shepherd’s results for one-row exchangers, are used to transform the local mass transfer coefficients into local heat transfer coefficients. A numerical two-dimensional heat transfer analysis has been performed in order to obtain the temperature distribution and fin efficiency. The influences of the Reynolds number and fin material are also analyzed.

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