Numerical Simulation and Experimental Validation of a Vertical U-Tube Ground Heat Exchanger

Abstract:

Vertical U-tube ground heat exchanger (GHE) is a key component in geothermal energy utilization systems like ground source heat pump (GSHP). This paper used a two-dimensional transient mathematical model for predicting the heat extraction rate of a vertical U-tube GHE, which also took into account the temperature distribution under the ground. Furthermore the modelling predictions were validated using experimental data. The experimental validation on the model was performed in a GSHP system with a double U-tube GHE, which was of 55m depth. For temperature distribution under the ground, the absolute error and relative error between experiment and simulation are within 0.62°C and 3.71 %. Simulation results agreed well with the experimental results that validate the feasibility of the mathematical model.

• Periodical: Advanced Materials Research (Volumes 860-863)
• Pages: 709-714
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.860-863.709
• Online since: December 2013
• Authors: Yi Ke Gao*, Yan Gao, Yong Yu, Xin Xing Lin
• Keywords: Experimental Verification, Ground Heat Exchanger (GHE), Numerical Simulation

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