A transient three-dimensional numerical solution is developed to analyze the thermal performance of thermo-active foundations used to heat and cool commercial buildings. Using laboratory testing data, the numerical solution is validated and used to carry out a sensitivity analysis to assess the most important design and operating parameters that affect the thermal performance of thermo-active foundations. It is found that the foundation depth, the shank space, the fluid flow rate, and the number of U-tube loops in each foundation pile are the main parameters that affect the thermal performance of a thermo-active foundation system. Based on the validated numerical solution, thermal response factors for a thermo-active foundation are developed, and implemented into a detailed building energy simulation program. These thermal response factors are then used to estimate the impact of installing thermo-active foundations on the total energy use of typical office buildings in representative US climates.

References

References
1.
Kusuda
,
T.
, and
Achenbach
,
P. R.
,
1965
, “
Earth Temperature and Thermal Diffusivity at Selected Stations in the United States
,”
ASHRAE Trans.
,
71
, pp.
120
131
.
2.
Krarti
,
M.
,
1999
, “
Ground-Coupled Heat Transfer
,”
Advances in Solar Energy
, Y. Goswami and K. Boer, eds.,
ASES
,
Boulder, CO
.
3.
ASHRAE
,
2009
,
ASHRAE Handbook of Fundamentals
, American Society for Heating,
Refrigerating, and Air Conditioning Engineers Inc.
,
Atlanta, GA
.
4.
US Department of Energy
, “Geothermal Technologies Program: Geothermal Basics,” accessed June 2012, http://www1.eere.energy.gov/geothermal/geothermal_basics.html.
5.
Brandl
,
H.
,
2006
, “
Energy Foundations and Other Thermo-Active Ground Structures
,”
Geotechnique
,
56
(
2
), pp.
81
122
.10.1680/geot.2006.56.2.81
6.
Laloui
,
L.
,
Nuth
,
M.
, and
Vulliet
,
L.
,
2006
, “
Experimental, Numerical Investigations of the Behaviour of a Heat Exchanger Pile
,”
Int. J. Numer. Anal. Methods Geomech
.
30
(
8
), pp.
763
781
.10.1002/nag.499
7.
Ooka
,
R.
,
Sekine
,
K.
,
Mutsumi
,
Y.
,
Yoshiro
,
S.
, and
SuckHo
,
H.
,
2007
, “
Development of a Ground Source Heat Pump System With Ground Heat Exchanger Utilizing the Cast in Place Concrete Pile Foundations of a Building
,” EcoStock 2006, Stockton, NJ, May 31–June 2.
8.
Adam
,
D.
, and
Markiewicz
,
R.
,
2009
, “
Energy From Earth-Coupled Structures, Foundations, Tunnels and Sewers
,”
Géotechnique
,
59
(
3
), pp.
229
236
.10.1680/geot.2009.59.3.229
9.
McCartney
,
J. S.
,
LaHaise
,
D.
,
LaHaise
,
T.
, and
Rosenberg
J. E.
,
2010
, “
Feasibility of Incorporating Geothermal Heat Sinks/Sources Into Deep Foundations
,”
The Art of Foundation Engineering Practice
,
M.
Hussein
,
W.
Camp
, and
J.
Anderson
, eds.
ASCE Geotechnical Special Publication
, Reston, VA, p.
198
.
10.
McCartney
,
J. S.
,
2010
, “
Centrifuge Modeling of Soil-Structure Interaction in Geothermal Foundations
,” NSF Report, University of Colorado, Boulder, CO.
11.
Kaltreider
,
C.
,
2011
, “
Heat Transfer Analysis of Thermo-Active Foundations
,” MS thesis, University of Colorado, Boulder, CO.
12.
Rouissi
,
K.
,
Krarti
,
M.
, and
McCartney
,
J. S.
,
2011
, “
Analysis of Thermo-Active Foundation Using U-Tube Heat Exchangers
,”
ASME J. Sol. Energy Eng.
,
134
(
2
), pp.
154
161
.10.1115/1.4005755
13.
Laloui
,
L.
,
Nuth
,
M.
, and
Vulliet
,
L.
,
2006
, “
Experimental, Numerical Investigations of the Behaviour of a Heat Exchanger Pile
,”
Int. Int. J. Numer. Analyt. Meth. Geomech.
30
(
8
), pp.
763
781
.10.1002/nag.499
14.
Hamada
,
Y.
,
Nakamura
,
M.
,
Kubota
,
H.
, and
Ochifuji
,
K.
,
2007
, “
Field Performance of an Energy Pile System for Space Heating
,”
Energy Build.
,
39
(
5
), pp.
517
524
.10.1016/j.enbuild.2006.09.006
15.
Sekine
,
K.
,
Oaka
,
R.
,
Yokoi
,
M.
,
Shiba
,
Y.
, and
Hwang
,
S.
,
2007
, “
Development of a Ground-Source Heat Pump System With Ground Heat Exchanger Utilizing the Cast-in-Place Concrete Pile Foundations of Buildings
,”
ASHRAE Trans.
, DA-07-061, pp.
558
566
.
16.
Wood
,
J. C.
,
Liu
,
H.
, and
Riffat
,
S. B.
,
2010
, “
An Investigation of the Heat Pump Performance and Ground Temperature of a Piled Foundation Heat Exchanger System for a Residential Building
,”
Energy
,
25
, pp.
4932
4940
.10.1016/j.energy.2010.08.032
17.
Jalaluddin
,
M. A.
,
Tsubaki
,
K.
,
Inoue
,
S.
, and
Yoshida
,
K.
,
2011
, “
Experimental Study of Several Types of Ground Heat Exchanger Using a Steel Pile Foundation
,”
Renewable Energy
,
36
, pp.
764
771
.10.1016/j.renene.2010.08.011
18.
Yavuzturk
,
C.
, and
Spitler
,
J. D.
,
1999
, “
A Short Time Step Response Factor Model For Vertical Ground Loop Heat Exchangers
,”
ASHRAE Trans.
,
105
(
2
), pp.
465
474
.
19.
Yavuzturk
,
C.
,
Spitler
,
J. D.
, and
Rees
,
S. J.
, “
A Transient Two-Dimensional Finite Volume Model for the Simulation of Vertical U-Tube Ground Heat Exchangers
,”
ASHRAE Trans.
,
105
(
2
). pp.
475
485
.
20.
Eskilson
,
P.
,
1987
, “
Thermal Analysis of Heat Extraction Boreholes
,” Doctoral thesis, Department of Mathematical Physics, University of Lund, Lund, Sweden.
21.
Kavanaugh
,
S.
,
2010
,
An Instruction Guide for Using a Design Tool for Vertical Ground-Coupled, Groundwater and Surface Water Heat Pumps Systems—Ground Source Heat Pump System Designer, GshpCalc Version 5.0. Energy Information Services, Northport, AL
,
http://
www.geokiss.com
22.
EnergyPlus
,
2009
, Engineering Reference, Department of Energy, Energy Efficiency and Renewable Energy, Building Technologies Program, Washington DC, http://apps1.eere.energy.gov/buildings/energyplus/
23.
WaterFurnace Inc.
,
2012
, Heat Pump Product Catalog—Hydronic NSW, Hydronic NDW, http://www.waterfurnace.com/literature/envision/SC1007WN.pdf
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