Calculation of Borehole Thermal Resistance

Research output: Chapter in Book/Report/Conference proceedingBook chapter

Abstract

The borehole thermal resistance – that is, the thermal resistance between the fluid in the U-tube and the borehole wall – is a key performance characteristic of a closed-loop borehole ground heat exchanger. Lower borehole thermal resistance leads to better system performance. Since the original identification of the concept borehole thermal resistance by Mogensen (1983), there have been numerous methods proposed for calculating this. In this chapter, we present methods for calculating local borehole thermal resistance and effective borehole thermal resistance which account for short-circuiting between the upward and downward-flowing legs of the ground heat exchanger. We also compare a wide range of simple, relatively easy-to-calculate methods to a detailed reference method and recommend suitable simplified methods.

Details

Authors
Organisations
Research areas and keywords

Subject classification (UKÄ) – MANDATORY

  • Energy Engineering
  • Energy Systems
  • Building Technologies

Keywords

  • Borehole thermal resistance, Grout resistance, Local Resistance, Effective resistance
Original languageEnglish
Title of host publicationAdvances in Ground-Source Heat Pump Systems.
EditorsSimon Rees
PublisherWoodhead Publishing Limited
Pages63-95
Edition1
ISBN (Print)978-0-08-100311-4
Publication statusPublished - 2016
Publication categoryResearch
Peer-reviewedYes

Publication series

NameWoodhead Publishing Series in Energy
PublisherElsevier under the Woodhead Publishing imprint