Thermal Science

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STUDY ON THE SIMPLIFIED MODEL OF VERTICAL DOUBLE U-PIPE GROUND HEAT EXCHANGER

ABSTRACT

A simplified semi-analytical model of vertical double U-pipe ground heat exchanger was established. The validity of the established model is examined by contrasting the figured outcomes with experiment data, emulation results of 3-D numerical model and calculation results of infinite line-source model for different inlet boundary conditions and configurations. After one hour, the semi-analytical model’s relative error is less than 0.32% under the boundary condition of given inlet fluid temperature. Under the boundary condition of given total heat input rate, the semi-analytical model’s relative error after ten hours is less than 0.11%, while the infinite line-source model’s relative error is less than 0.60%. The semi-analytical model is in good agreement with experiment and numerical model, and has higher calculation accuracy than infinite line-source model.

KEYWORDS

verticaldouble U-pipe ground heat exchanger (VDUGHE), semi-analytical model, heat transfer, temperature distribution

PAPER SUBMITTED: 2022-09-22

PAPER REVISED: 2022-12-15

PAPER ACCEPTED: 2022-12-22

PUBLISHED ONLINE: 2023-03-11

DOI REFERENCE: https://doi.org/10.2298/TSCI220922048W

CITATION EXPORT: view in browser or download as text file

THERMAL SCIENCE YEAR 2023, VOLUME 27, ISSUE No. 5, PAGES [4035 - 4048]

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Study on the simplified model of vertical double U-pipe ground heat exchanger

© 2026 Society of Thermal Engineers of Serbia. Published by the Vinča Institute of Nuclear Sciences, National Institute of the Republic of Serbia, Belgrade, Serbia. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution-NonCommercial-NoDerivs 4.0 International licence

THERMAL SCIENCE

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Xin Wang

Qiang Fu

Changlong Wang

STUDY ON THE SIMPLIFIED MODEL OF VERTICAL DOUBLE U-PIPE GROUND HEAT EXCHANGER