Calculation of Borehole Thermal Resistance
Book chapter, 2016

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.

effective resistance

borehole thermal resistance

multipole

grout resistance

local resistance

comparison

calculation

resistance network

Author

Saqib Javed

Chalmers, Civil and Environmental Engineering, Building Services Engineering

Jeff Spitler

Oklahoma State University - Stillwater

Advances in Ground-Source Heat Pump Systems

63-95

Subject Categories

Mechanical Engineering

Energy Engineering

Environmental Engineering

Energy Systems

Building Technologies

Driving Forces

Sustainable development

Areas of Advance

Building Futures (2010-2018)

Energy

DOI

10.1016/B978-0-08-100311-4.00003-0

ISBN

978-0-08-100322-0

More information

Created

10/8/2017