In Situ Testing and Analysis of Thermal Properties of the Ground Formation in Jiangsu, China

Abstract:

Ground source heat pump (GSHP) systems exchange heat with the ground, often through a closed-loop, vertical, borehole heat exchanger (BHE). The performance of the BHE depends on the thermal properties of the ground formation, as well as soil or backfill in the borehole. The design and economic probability of GSHP systems need the thermal conductivity of geological structure and thermal resistance of BHE. Thermal response test (TRT) method allows the in-situ determination of the thermal conductivity (λ) of the ground formation in the vicinity of a BHE, as well as the effective thermal resistance (R_b) of this latter. Thermal properties measured in laboratory experiments do not comply with data of in-situ conditions. The present article describes the results of thermal properties of the BHE whose depth is 100m in Yancheng City, Jiangsu Province, China. As shown in these results, λ and R_b of borehole are determined as 1.84(W·m^-1·K^-1) and 0.121 (m·K·W^-1) respectively.

• Periodical: Advanced Materials Research (Volume 933)
• Pages: 477-481
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.933.477
• Online since: May 2014
• Authors: Shuai Chen*
• Keywords: Ground Source Heat Pump (GSHP), Thermal Conductivity, Thermal Resistance, Thermal Response Test, Vertical Heat Exchanger

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