Comparing the thermal performance of horizontal slinky-loop and vertical slinky-loop heat exchangers

Chong, C. S. A., Gan, G., Verhoef, A. ORCID: https://orcid.org/0000-0002-9498-6696 and Gonzalez Garcia, R. G. (2013) Comparing the thermal performance of horizontal slinky-loop and vertical slinky-loop heat exchangers. International Journal of Low-Carbon Technology, 9 (4). pp. 250-255. ISSN 1748-1325 doi: 10.1093/ijlct/ctt001

Abstract/Summary

The heat pump market in the UK has grown rapidly over the last few years. Performance analyses of vertical ground-loop heat exchanger configurations have been widely carried out using both numerical modelling and experiments. However, research findings and design recommendations on horizontal slinky-loop and vertical slinky-loop heat exchangers are far fewer compared with those for vertical ground-loop heat exchanger configurations, especially where the long-term operation of the systems is concerned. The paper presents the results obtained from a numerical simulation for the horizontal slinky-loop and vertical slinky-loop heat exchangers of a ground-source heat pump system. A three-dimensional numerical heat transfer model was developed to study the thermal performance of various heat exchanger configurations. The influence of the loop pitch (loop spacing) and the depth of a vertical slinky-loop installation were investigated and the thermal performance and excavation work required for the horizontal and vertical slinky-loop heat exchangers were compared. The influence of the installation depth for vertical slinky-loop configurations was also investigated. The results of this study show that the influence of the installation depth of the vertical slinky-loop heat exchanger on the thermal performance of the system is small. The maximum difference in the thermal performance between the vertical and horizontal slinky-loop heat exchangers with the same loop diameter and loop pitch is less than 5%.