Browsing Proceedings of the IGSHPA Technical/Research Conference and Expo 2017 by Title
Now showing items 18-37 of 44
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Heat extraction distributed thermal response test: A methodological approach and in-situ experiment
(International Ground Source Heat Pump Association, 2017)The Thermal Response Test (TRT) is a worldwide adopted in-situ methodology able to estimate the ground thermal conductivity and borehole thermal resistance. During the test the carrier-fluid exchanges a constant heat flux ... -
Heat pump capacity effects on peak electricity consumption and total length of self- and solar-assisted shallow ground heat exchanger networks
(International Ground Source Heat Pump Association, 2017)A new "self-assisted" Ground Source Heat Pump (GSHP) system configuration is proposed to address the relatively high peak electricity demand of undersized GSHP systems equipped with auxiliary electric heater. In this ... -
High time-resolution analytical models for heat transfer through U-shaped ground heat exchangers
(International Ground Source Heat Pump Association, 2017)This paper reports a set of high time-resolution analytical models for heat transfer of GHEs, including a full scale line-source model for heat transfer outside U-shaped pipes and a quasi-3D heat transfer model for the ... -
Improving thermal conductivity and fluid loss properties of grouting materials: New mixed grout granules of bentonites and sands
(International Ground Source Heat Pump Association, 2017)We propose new granule type grouting materials with optimized ratio of bentonites and sands for use in the ground source heat pump systems. The grouting materials could be prepared in various size of 1.18 to 4.75 mm. The ... -
Influence of different ground thermal properties in a borehole heat exchanger's performance using the B2G dynamic model
(International Ground Source Heat Pump Association, 2017)Ground source heat pump (GSHP) systems for heating and cooling represent an efficient alternative to conventional air source heat pump systems, always provided that they present an efficient design and operation. In this ... -
Influence of ground heat exchanger zoning operation on the GSHP system long-term operation performance
(International Ground Source Heat Pump Association, 2017)To alleviate the ground heat accumulation after long term running of ground source heat pumps (GSHP), ground heat exchanger (GHE) zoning operation can be adopted. Two GHE operation modes - zoning operation and full running ... -
Investigation of thermo-hydro-geochemical processes in a standing column well intersected by a fracture
(International Ground Source Heat Pump Association, 2017)Local thermal and chemical conditions may favor minerals' scaling which can cause undesirable operational problems to standing column well systems. Precipitation may reduce heat exchange in the well and the heat exchanger ... -
Investigation on the effects of different time resolutions in the design and simulation of BHE fields
(International Ground Source Heat Pump Association, 2017)The correct design of a field of Borehole Heat Exch angers (BHE) requires the knowledge of ground thermal properties, heat pump performance and building heating and cooling demand. The sequence o f heat pulses from (to) ... -
Measurement of internal and effective borehole resistances during thermal response tests
(International Ground Source Heat Pump Association, 2017)In a conventional thermal response test (TRT), the main parameter evaluated is the bulk subsurface thermal conductivity surrounding the borehole. It is also possible to evaluate the borehole thermal resistance. Several ... -
Minimum well separation for small groundwater heat pump (GWHP) systems in Korea: Preliminary analysis based on regional aquifer properties
(International Ground Source Heat Pump Association, 2017)Shallow geothermal energy has been estimated to have an excellent applicability in Korea, and its applications for space heating and cooling have steadily increased in recent years. Such application as ground source heat ... -
Model for ground temperature estimations and its impact on horizontal ground heat exchanger design
(International Ground Source Heat Pump Association, 2017)The ground-source heat pump systems are highly efficient and energy saving. Its main disadvantage is a significantly higher installation cost compared to conventional systems. The length of the ground heat exchanger (GHX) ... -
Modelling and experimental validation of a novel co-axial spiral borehole heat exchanger
(International Ground Source Heat Pump Association, 2017)In order to optimize the operation of a ground source heat pump (GSHP) system, the development of dynamic models that integrate all the system components is a key factor. Particularly, the modelling of the ground source ... -
Modelling of alternative borehole configurations for geo-exchange
(International Ground Source Heat Pump Association, 2017)During the operation of a ground source heat pump (GSHP), the ground acts as a heat sink and heat source in cooling and heating modes, respectively. When the heating and cooling loads are extremely unbalanced, ground ... -
Nanocomposite materials used for ground heat exchanger pipes
(International Ground Source Heat Pump Association, 2017)This study compares the performance of single U-pipe, double U-pipe, and coaxial ground heat exchangers (GHE) equipped with standard HDPE and thermally enhanced (TE) pipes. Sizing calculations and 10-year hourly simulations ... -
New methods to spatially extend thermal response test assessments
(International Ground Source Heat Pump Association, 2017)Thermal response tests (TRTs), used to evaluate the subsurface thermal conductivity when designing ground source heat pump systems, are spatially limited to the vicinity of the borehole where a test is carried out. The ... -
Numerical investigation on the thermo-mechanical behavior of a quadratic cross section pile heat exchanger
(International Ground Source Heat Pump Association, 2017)Pile heat exchangers are traditional foundation piles with built in heat exchangers. As such, the footing of the building both serves as a structural component and a heating/cooling supply element. The existing geotechnical ... -
Numerical simulation of pile geothermal heat exchanger with spiral tube considering its thermo-mechanical behavior
(International Ground Source Heat Pump Association, 2017)Pile geothermal heat exchanger (PGHE), which utilizes the building foundation piles as part of the geothermal heat exchangers (GHEs) for a ground-coupled heat pump (GCHP) system, has been attracting the interests of ... -
Optimal control and operation of a GSHP system for heating and cooling in an office building
(International Ground Source Heat Pump Association, 2017)Ground source heat pump (GSHP) systems are widely considered as being among the most efficient heating and cooling renewable technologies currently available. Nevertheless, both an optimal design of components and an optimal ... -
Properties of different ethyl alcohol based secondary fluids used for GSHP in Europe and USA
(International Ground Source Heat Pump Association, 2017)The extensive use of ground source heat pumps (GSHP) for heating and cooling purposes has made Sweden the European leader in geothermal energy utilization, in terms of the installed capacity, as well as extracted thermal ... -
Providing low carbon cooling through pile foundations; the effect of thermal cycling on clay strength
(International Ground Source Heat Pump Association, 2017)Pile foundations provide a low-intrusive mechanism for installing heat exchangers into the ground, especially if the piles are being installed to support the building. The ground temperature is relatively constant at depths ...