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Second-Order Multipole Formulas for Thermal Resistance of Single U-tube Borehole Heat Exchangers

S, Javed LU and Claesson, Johan LU (2017) Research Conference Proceedings - IGSHPA Conference & Expo 2017 p.102-112
Abstract
The borehole thermal resistance is both an important design parameter and a key performance characteristic of a borehole heat exchanger. Another quantity that is particularly important for deep borehole heat exchangers is the internal thermal resistance between the upward-flowing and downward-flowing fluid channels in the borehole. The multipole method is a well-known and robust method to compute both these thermal resistances. However, it has a fairly intricate mathematical algorithm and is thus not trivial to implement. Consequently, there is considerable interest in developing explicit multipole formulas. So far zeroth-order and first-order multipole formulas have been derived for cases where the two legs of the borehole are placed... (More)
The borehole thermal resistance is both an important design parameter and a key performance characteristic of a borehole heat exchanger. Another quantity that is particularly important for deep borehole heat exchangers is the internal thermal resistance between the upward-flowing and downward-flowing fluid channels in the borehole. The multipole method is a well-known and robust method to compute both these thermal resistances. However, it has a fairly intricate mathematical algorithm and is thus not trivial to implement. Consequently, there is considerable interest in developing explicit multipole formulas. So far zeroth-order and first-order multipole formulas have been derived for cases where the two legs of the borehole are placed symmetrically in a borehole. This paper presents new explicit second-order multipole formulas, which provide significant accuracy improvements over the previous formulas. (Less)
Please use this url to cite or link to this publication:
author
and
organization
publishing date
type
Chapter in Book/Report/Conference proceeding
publication status
published
subject
keywords
Borehole thermal resistance, Multipole method, Ground heat exchanger, Internal thermal resistance, Second-order multipole formulas
host publication
Research Conference Proceedings, International Ground Source Heat Pump Association Conference & Expo, March 14-16, 2017
pages
102 - 112
conference name
Research Conference Proceedings - IGSHPA Conference & Expo 2017
conference location
Denver, United States
conference dates
2017-03-14 - 2017-03-16
DOI
10.22488/okstate.17.000535
language
English
LU publication?
yes
id
9f08ba87-d36d-4dcc-9129-b5a20c3550b5
date added to LUP
2017-03-16 22:40:03
date last changed
2018-11-21 21:30:47
@inproceedings{9f08ba87-d36d-4dcc-9129-b5a20c3550b5,
  abstract     = {{The borehole thermal resistance is both an important design parameter and a key performance characteristic of a borehole heat exchanger. Another quantity that is particularly important for deep borehole heat exchangers is the internal thermal resistance between the upward-flowing and downward-flowing fluid channels in the borehole. The multipole method is a well-known and robust method to compute both these thermal resistances. However, it has a fairly intricate mathematical algorithm and is thus not trivial to implement. Consequently, there is considerable interest in developing explicit multipole formulas. So far zeroth-order and first-order multipole formulas have been derived for cases where the two legs of the borehole are placed symmetrically in a borehole. This paper presents new explicit second-order multipole formulas, which provide significant accuracy improvements over the previous formulas.}},
  author       = {{S, Javed and Claesson, Johan}},
  booktitle    = {{Research Conference Proceedings, International Ground Source Heat Pump Association Conference & Expo, March 14-16, 2017}},
  keywords     = {{Borehole thermal resistance, Multipole method, Ground heat exchanger, Internal thermal resistance, Second-order multipole formulas}},
  language     = {{eng}},
  month        = {{03}},
  pages        = {{102--112}},
  title        = {{Second-Order Multipole Formulas for Thermal Resistance of Single U-tube Borehole Heat Exchangers}},
  url          = {{http://dx.doi.org/10.22488/okstate.17.000535}},
  doi          = {{10.22488/okstate.17.000535}},
  year         = {{2017}},
}