Finite line-source model for borehole heat exchangers: effect of vertical temperature variations

Bandos, Tatyana V.; Montero, Álvaro; Fernández, Esther; Santander, J. L. G.; Isidro, J. M.; Pérez, Joaquín; Córdoba, Pedro Fernández de; Urchueguı́a, Javier F.

doi:10.1016/j.geothermics.2009.01.003

Cited by 168 publications

(102 citation statements)

References 16 publications

Supporting

Mentioning

100

Contrasting

Unclassified

Order By: Relevance

“…This accessible design approach has helped the adoption of borehole heat exchangers across many parts of the world, but especially northern Europe and North America. Some improvements have been made to the basic Gfunction concept since then; for example Bandos et al [3] have developed a method to include fluctuations in the ground surface temperature and the UK Partners in Innovation Project [4] developed software which allowed direct superposition of the single borehole G-functions in order to remove the need to interpolate between pre-programmed curves. However, the fundamental approach has remained unchanged.…”

Section: Existing Design Approachesmentioning

confidence: 99%

Temperature response functions (G-functions) for single pile heat exchangers

Loveridge

Powrie

2013

Energy

108

View full text Add to dashboard Cite

Foundation piles used as heat exchangers as part of a ground energy system have the potential to reduce energy use and carbon dioxide emissions from new buildings. However, current design approaches for pile heat exchangers are based on methods developed for boreholes which have a different geometry, with a much larger aspect (length to diameter) ratio. Current methods also neglect the transient behaviour of the pile concrete, instead assuming a steady state resistance for design purposes. As piles have a much larger volume of concrete than boreholes, this neglects the significant potential for heat storage within the pile. To overcome these shortcomings this paper presents new pile temperature response functions (G-functions) which are designed to reflect typical geometries of pile heat exchangers and include the transient response of the pile concrete. Owing to the larger number of pile sizes and pipe configurations which are possible with pile heat exchangers it is not feasible to developed a single unified G-function and instead upper and lower bound solutions are provided for different aspects ratios. (172 words)

show abstract

Section: Existing Design Approachesmentioning

confidence: 99%

Temperature response functions (G-functions) for single pile heat exchangers

Loveridge

Powrie

2013

Energy

108

View full text Add to dashboard Cite

show abstract

“…It is usually assumed that the heat is released at a constant rate from the borehole heat exchanger (BHE), in the 'radial' direction orthogonal to it, and is transferred by the mechanism of thermal conductivity. In the frame of the finite line-source (FLS) model in the semi-infinite region, the approximation of the ground temperature, averaged along the BHE, for the times corresponding to the TRT was proposed by Bandos et al (2009a the characteristic axial time scale and H is the borehole depth. The acquisition system used to monitor the ground thermal response was connected to the borehole heat exchanger by insulated 1-m long tubes.…”

Section: Improving Data Analysis Toolsmentioning

confidence: 99%

“…One approach consists in refining the model describing the borehole heat exchanger to include effects not taken into account. Finite length effects can be incorporated in the analysis procedure of test in situ outputs as shown in Bandos et al (2008a), Bandos et al (2008b) and Bandos et al (2009a). A filtering technique of the undesired effect produced in temperature measurements by the ambient temperature can be used to improve the estimating of ground thermal properties (Bandos et al (2009b), Bandos et al (2009c), Bandos et al (2009d)).…”

Section: Introductionmentioning

confidence: 99%

Ground Coupled Heat Pumps in Mixed Climate Areas: Design, Characterization and Optimization

Montero¹,

Bandos²,

Magraner³

et al. 2010

Paths to Sustainable Energy

View full text Add to dashboard Cite

“…It was shown that the value of thermal response factors are sensitive to the borehole thermal resistance. Furthermore, the condition of constant ground surface temperature may also lead to inaccuracies when predicting fluid and ground temperatures in geothermal systems (Bandos, et al 2009;Bandos, et al 2011;Rivera, et al 2015;Zarrella and Pasquier 2015;Rivera, et al 2016).…”

Section: Introductionmentioning

confidence: 99%