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http://dx.doi.org/10.7843/kgs.2012.28.12.5

Evaluation of Ground Thermal Conductivity by Performing In-Situ Thermal Response test (TRT) and CFD Back-Analysis  

Park, Moonseo (School of Civil, Environmental and Architectural Engineering, Korea Univ.)
Lee, Chulho (BK21, Korea Univ.)
Park, Sangwoo (School of Civil, Environmental and Architectural Engineering, Korea Univ.)
Sohn, Byonghu (Green Building Research Division, Korea Institute of Construction Technology)
Choi, Hangseok (School of Civil, Environmental and Architectural Engineering, Korea Univ.)
Publication Information
Journal of the Korean Geotechnical Society / v.28, no.12, 2012 , pp. 5-15 More about this Journal
Abstract
In this study, a series of CFD (Computational Fluid Dynamics) numerical analyses were performed in order to evaluate the thermal performance of six full-scale closed-loop vertical ground heat exchangers constructed in a test bed located in Wonju. The circulation HDPE pipe, borehole and surrounding ground formation were modeled using FLUENT, a finite-volume method (FVM) program, for analyzing the heat transfer process of the system. Two user-defined functions (UDFs) accounting for the difference in the temperatures of the circulating inflow and outflow fluid and the variation of the surrounding ground temperature with depth were adopted in the FLUENT model. The relevant thermal properties of materials measured in laboratory were used in the numerical analyses to compare the thermal efficiency of various types of the heat exchangers installed in the test bed. The simulation results provide a verification for the in-situ thermal response test (TRT) data. The CFD numerical back-analysis with the ground thermal conductivity of 4 W/mK yielded better agreement with the in-situ thermal response tests than with the ground thermal conductivity of 3 W/mK.
Keywords
Back-analysis; Bentonite grout; Cement grout; Closed-loop vertical ground heat exchanger; Thermal response test; Thermal conductivity;
Citations & Related Records
Times Cited By KSCI : 6  (Citation Analysis)
연도 인용수 순위
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