Ground-Coupled Natural Circulating Devices (Thermosiphons): A Review of Modeling, Experimental and Development Studies

Compared to conventional ground heat exchangers that require a separate pump or othermechanical devices to circulate the heat transfer fluid, ground coupled thermosiphons or naturallycirculating ground heat exchangers do not require additional equipment for fluid circulation in theloop. This might lead to a better overall efficiency and much simpler operation. This paper providesa review of the current published literature on the different types of existing ground coupledthermosiphons for use in applications requiring moderate and low temperatures. Effort has beenfocused on their classification according to type, configurations, major designs, and chronologicalyear of apparition. Important technological findings and characteristics are provided in summarytables. Advances are identified in terms of the latest device developments and innovative conceptsof thermosiphon technology used for the heat transfer to and from the soil. Applications arepresented in a novel, well-defined classification in which major ground coupled thermosiphonapplications are categorized in terms of medium and low temperature technologies. Finally,performance evaluation is meticulously discussed in terms of modeling, simulations, parametric,and experimental studies.

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Analysis and Comparison of Some Low-Temperature Heat Sources for Heat Pumps

Energies ◽

10.3390/en12101853 ◽

2019 ◽

Vol 12 (10) ◽

pp. 1853 ◽

Cited By ~ 3

Author(s):

Pavel Neuberger ◽

Radomír Adamovský

Keyword(s):

Heat Transfer ◽

Low Temperature ◽

Heat Source ◽

Heat Pump ◽

Heat Exchangers ◽

Ambient Air ◽

Heat Transfer Fluid ◽

Heat Sources ◽

Ground Heat Exchangers ◽

Temperature Heat

The efficiency of a heat pump energy system is significantly influenced by its low-temperature heat source. This paper presents the results of operational monitoring, analysis and comparison of heat transfer fluid temperatures, outputs and extracted energies at the most widely used low temperature heat sources within 218 days of a heating period. The monitoring involved horizontal ground heat exchangers (HGHEs) of linear and Slinky type, vertical ground heat exchangers (VGHEs) with single and double U-tube exchanger as well as the ambient air. The results of the verification indicated that it was not possible to specify clearly the most advantageous low-temperature heat source that meets the requirements of the efficiency of the heat pump operation. The highest average heat transfer fluid temperatures were achieved at linear HGHE (8.13 ± 4.50 °C) and double U-tube VGHE (8.13 ± 3.12 °C). The highest average specific heat output 59.97 ± 41.80 W/m2 and specific energy extracted from the ground mass 2723.40 ± 1785.58 kJ/m2·day were recorded at single U-tube VGHE. The lowest thermal resistance value of 0.07 K·m2/W, specifying the efficiency of the heat transfer process between the ground mass and the heat transfer fluid, was monitored at linear HGHE. The use of ambient air as a low-temperature heat pump source was considered to be the least advantageous in terms of its temperature parameters.

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Experimental studies on micro-channel heat sink with different heat transfer fluid

10.1063/5.0036125 ◽

2021 ◽

Author(s):

M. P. Dhanishk ◽

P. Selvakumar ◽

V. Ashwin ◽

P. N. ArunKumar

Keyword(s):

Heat Transfer ◽

Heat Sink ◽

Experimental Studies ◽

Heat Transfer Fluid ◽

Micro Channel

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Call for Nominations – The Nusselt–Reynolds Prize Sponsored by Assembly of World Conferences on Experimental Heat Transfer, Fluid Mechanics, and Thermodynamics

Journal of Fluid Mechanics ◽

10.1017/s0022112099007454 ◽

2000 ◽

Vol 402 ◽

pp. 382-382

Author(s):

Nobuhide Kasagi

Keyword(s):

Heat Transfer ◽

Fluid Mechanics ◽

Design Theory ◽

Experimental Studies ◽

Heat Transfer Fluid ◽

World Conference ◽

Experimental Heat ◽

Technological Advances ◽

Visualization Techniques ◽

Physical Phenomena

The Nusselt–Reynolds Prize has been established by the Assembly of World Conferences to commemorate outstanding contributions by Wilhelm Nusselt and Osborne Reynolds as experimentalists, researchers, educators, and authors. As many as three prizes may be bestowed at every World Conference, one in each of the areas of heat transfer, fluid mechanics, thermodynamics, or any combination of these.The prize will be bestowed for outstanding scientific and engineering contributions and eminent achievements in the fields of heat transfer, fluid mechanics, and thermodynamics through (1) experimental studies and analytical/numerical extension of the measurements, (2) development of experimental techniques, visualization techniques, and/or instrumentation, and/or (3) development of design theory (that needs experimental data) and theory-based experimental correlations. These contributions should yield a deeper insight into physical phenomena involved or should yield significant technological advances. In addition to research, the awardee(s) should have made outstanding contributions to the field through teaching, design, or a combination of such activities. The prize is based on achievement through publications or through the application of the science or art. Nationality, age, sex, and society membership will not be considered when evaluating qualifications of candidates. A candidate must be living at the time of designation as a recipient of the prize.The prize consists of a bronze plaque, and engrossed certificate, and an honorarium. The prize is administered by the Prize Board. The deadline for accepting nominations for the Prize is February 2, 2000. The prize will be awarded at the Fifth World Conference during September 24–28, 2001 in Thessaloniki, Greece where the prize winners will also present plenary lectures on their subjects.Nominators can obtain further information and download the nomination form from a webpage at http://www.thtlab.t.u-tokyo.ac.jp/N-Rprize.html/.

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Analysis of Heat Exchanger Concepts for Use As Gas Turbine Intercoolers

10.1115/imece2001/htd-24321 ◽

2001 ◽

Author(s):

Arash Saidi ◽

Daniel Eriksson ◽

Bengt Sundén

Keyword(s):

Heat Transfer ◽

Heat Exchanger ◽

Pressure Drop ◽

Gas Turbine ◽

Power Output ◽

Heat Exchangers ◽

Advantages And Disadvantages ◽

Volume Weight ◽

Different Types ◽

Core Volume

Abstract This paper presents a discussion and comparison of some heat exchanger types readily applicable to use as intercoolers in gas turbine systems. The present study concerns a heat duty of the intercooler for a gas turbine of around 17 MW power output. Four different types of air-water heat exchangers are considered. This selection is motivated because of the practical aspects of the problem. Each configuration is discussed and explained, regarding advantages and disadvantages. The available literature on the pressure drop and heat transfer correlations is used to determine the thermal-hydraulic performance of the various heat exchangers. Then a comparison of the intercooler core volume, weight, pressure drop is presented.

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Analysis of Heat Transfer by Pile and Borehole Ground Heat Exchangers: Composite-Medium Line-Source Approach

Lecture Notes in Electrical Engineering - Proceedings of the 8th International Symposium on Heating, Ventilation and Air Conditioning ◽

10.1007/978-3-642-39578-9_7 ◽

2013 ◽

pp. 55-62

Author(s):

Min Li ◽

Yi Yang

Keyword(s):

Heat Transfer ◽

Heat Exchangers ◽

Line Source ◽

Composite Medium ◽

Ground Heat Exchangers

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Corrosion and corrosion prevention in heat exchangers

Corrosion Reviews ◽

10.1515/corrrev-2018-0054 ◽

2019 ◽

Vol 37 (2) ◽

pp. 131-155 ◽

Cited By ~ 5

Author(s):

Willem Faes ◽

Steven Lecompte ◽

Zaaquib Yunus Ahmed ◽

Johan Van Bael ◽

Robbe Salenbien ◽

...

Keyword(s):

Heat Transfer ◽

Heat Exchangers ◽

Prevention And Control ◽

Metallic Materials ◽

Corrosion Prevention ◽

Design Considerations ◽

Repair Costs ◽

Anodic Protection ◽

Different Types ◽

And Control

AbstractIn many industries and processes, heat exchangers are of vital importance as they are used to transfer heat from one fluid to another. These fluids can be corrosive to heat exchangers, which are usually made of metallic materials. This paper illustrates that corrosion is an important problem in the operation of heat exchangers in many environments, for which no straightforward answer exists. Corrosion failures of heat exchangers are common, and corrosion often involves high maintenance or repair costs. In this review, an overview is given of what is known on corrosion in heat exchangers. The different types of corrosion encountered in heat exchangers and the susceptible places in the devices are discussed first. This is combined with an overview of failure analyses for each type of corrosion. Next, the effect of heat transfer on corrosion and the influence of corrosion on the thermohydraulic performances are discussed. Finally, the prevention and control of corrosion is tackled. Prevention goes from general design considerations and operation guidelines to the use of cathodic and anodic protection.

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Review of Artificial Bubble Generation Techniques and Their Suitability for Phenomenological Boiling Studies

ASME 2020 Heat Transfer Summer Conference ◽

10.1115/ht2020-9162 ◽

2020 ◽

Author(s):

Navdeep Singh Dhillon

Keyword(s):

Heat Transfer ◽

Fluid Flow ◽

Experimental Studies ◽

Solid Surfaces ◽

Interfacial Phenomena ◽

Heat Transfer Fluid ◽

Bubble Generation ◽

Multiple Bubbles

Abstract The heterogeneous boiling of liquids on hot surfaces, despite its importance, is an extremely complicated and murky phenomenon. It involves the random probabilistic nucleation of multiple bubbles whose growth, interaction, and departure, further, depends on processes involving heat transfer, fluid flow, and interfacial phenomena. This, and the random tumultuous nature of boiling makes experimental studies of the process extremely difficult. For achieving a phenomenological understanding of boiling, several researchers have relied on experiments involving artificially generated bubbles on solid surfaces. In this paper, we evaluate these methods of artificial bubble generation and explore how closely they replicate actual heterogeneous boiling conditions experienced by bubbles. Based on this, we assess the suitability of these methods for conducting phenomenological boiling studies, and identify their potential advantages and drawbacks.

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