A modified mathematical model for spiral coil-type horizontal ground heat exchangers. (1st June 2018)

• Record Type: Journal Article
• Authors: Jeon, Jun-Seo; Lee, Seung-Rae; Kim, Min-Jun
• Is Part Of: Energy. Volume 152(2018)
• Page Start: 732
• Page End: 743
• Publication Date: 2018-06-01
• Subjects: Spiral coil-type -- Horizontal ground heat exchanger -- Thermal response test -- Green's function -- Numerical simulation; Power resources -- Periodicals; Power (Mechanics) -- Periodicals; Energy consumption -- Periodicals; 333.7905
• DOI: 10.1016/j.energy.2018.04.007
• Languages: English
• ISSNs: 0360-5442

Abstract

Abstract: Although many studies have investigated spiral coil-type horizontal ground heat exchangers (HGHEs), a reliable mathematical model of them has not yet been developed. Accordingly, this study proposes a modification of existing mathematical model, which was originally developed for energy piles and vertical ground heat exchangers, for HGHEs. Based on the solution of the heat equation using Green's function, the new mathematical model was derived by employing the mirror image method and superposition to consider the effect of a semi-infinite medium and ground temperature distribution. The prediction of the mathematical model showed a good fit with the results from on-site experiments with a mean absolute percentage error of 0.30% and was perfectly matched with the numerical results. The proposed mathematical model is capable of capturing the structure of the spiral coil exactly, and consequently, it offers a more accurate prediction of ground temperature. Highlights: Mathematical model for spiral coil-type HGHEs was presented. Green's function, mirror image and superposition method were used. For validation, the on-site experiment and numerical simulation were employed. The proposed mathematical model provides more accurate results.