Influence of Time-Dependent Soil Thermal Conductivity on Performance Assessment of Energy Foundations
Publication: Geo-Congress 2023
ABSTRACT
Soil thermal conductivity k plays a significant role in performance assessment of energy geostructures that have direct or indirect thermal interaction with soil. Research presented herein uses a custom-made apparatus to determine both transient- and steady-state values of k from a single test. Results obtained from three different soils suggest that the steady-state k values are consistently higher than their transient-state counterparts. For all tested materials, transient-state k values are sensitive to the rate of soil temperature increment, whereas the values of steady-state k remain constant irrespective of the rate of transient heating. Numerical simulations of laboratory experiments suggest that the use of a time-dependent function of k predicts the experiment results adequately. Moreover, analyses demonstrate that the use of a transient-state k value may significantly underestimate power output from a geothermal pile.
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REFERENCES
Abu-Hamdeh, N. H., and Reeder, R. C. (2000). Soil thermal conductivity effects of density, moisture, salt concentration, and organic matter. Soil science society of America Journal, 64(4), 1285–1290.
Abuel-Naga, H. M., Bergado, D. T., Bouazza, A., and Pender, M. J. (2009). Thermal conductivity of soft Bangkok clay from laboratory and field measurements. Engineering Geology, 105(3-4), 211–219.
Alrtimi, A., Rouainia, M., and Manning, D. (2014). An improved steady-state apparatus for measuring thermal conductivity of soils. International Journal of Heat and Mass Transfer, 72, 630–636.
ASTM. ASTM D5334-14. (2014). D5334-14 Standard Test Method for Determination of Thermal Conductivity of Soil and Soft Rock by Thermal Needle Probe Procedure. ASTM International: West Conshohocken, PA, USA.
Chen, S. X. (2008). Thermal conductivity of sands. Heat and mass transfer, 44(10), 1241–1246.
Gangadhara Rao, M., and Singh, D. (1999). A generalized relationship to estimate thermal resistivity of soils. Canadian Geotechnical Journal, 36(4), 767–773.
Ghasemi-Fare, O., and Basu, P. (2018). Influences of ground saturation and thermal boundary condition on energy harvesting using geothermal piles. Energy and Buildings, 165, 340–351.
Giordano, N., Chicco, J., Mandrone, G., Verdoya, M., and Wheeler, W. H. (2019). Comparing transient and steady-state methods for the thermal conductivity characterization of a borehole heat exchanger field in Bergen, Norway. Environmental Earth Sciences, 78(15), 1–15.
Kerschbaumer, R. C., Stieger, S., Gschwandl, M., Hutterer, T., Fasching, M., Lechner, B., Meinhart, L., Hildenbrandt, J., Schrittesser, B., and Fuchs, P. F. (2019). Comparison of steady-state and transient thermal conductivity testing methods using different industrial rubber compounds. Polymer testing, 80, 106121.
Kramer, C. A., Ghasemi-Fare, O., and Basu, P. (2015). Laboratory thermal performance tests on a model heat exchanger pile in sand. Geotechnical and Geological Engineering, 33(2), 253–271.
Low, J. E., Loveridge, F. A., Powrie, W., and Nicholson, D. (2015). A comparison of laboratory and in situ methods to determine soil thermal conductivity for energy foundations and other ground heat exchanger applications. Acta geotechnica, 10(2), 209–218.
Mahdavi, S., Neyshabouri, M., and Fujimaki, H. (2019). A Spherical Steady-State Method to Measure Soil Thermal Conductivity. Eurasian Soil Science, 52(12), 1572–1576.
Park, K., Lee, J., Yoon, H.-K., and Kim, D. (2016). Hydraulic and thermal conductivities of kaolin–silica mixtures under different consolidation stresses. Marine Georesources & Geotechnology, 34(6), 532–541.
Roshankhah, S., Garcia, A. V., and Carlos Santamarina, J. (2021). Thermal Conductivity of Sand–Silt Mixtures. Journal of Geotechnical and Geoenvironmental Engineering, 147(2), 06020031.
Sass, J., Stone, C., and Munroe, R. J. (1984). Thermal conductivity determinations on solid rock—a comparison between a steady-state divided-bar apparatus and a commercial transient line-source device. Journal of Volcanology and Geothermal Research, 20(1-2), 145–153.
Tang, A.-M., Cui, Y.-J., and Le, T.-T. (2008). A study on the thermal conductivity of compacted bentonites. Applied Clay Science, 41(3-4), 181–189.
Xiao, Y., Liu, H., Nan, B., and McCartney, J. S. (2018). Gradation-dependent thermal conductivity of sands. Journal of Geotechnical and Geoenvironmental Engineering, 144(9).
Xu, Y., Zeng, Z., and Lv, H. (2019). Effect of temperature on thermal conductivity of lateritic clays over a wide temperature range. International Journal of Heat and Mass Transfer, 138, 562–570.
Yu, X., Zhang, N., Pradhan, A., and Puppala, A. J. (2016). Thermal conductivity of sand–kaolin clay mixtures. Environmental Geotechnics, 3(4), 190–202.
Zhang, M., Lu, J., Lai, Y., and Zhang, X. (2018). Variation of the thermal conductivity of a silty clay during a freezing-thawing process. International Journal of Heat and Mass Transfer, 124, 1059–1067.
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Geo-Congress 2023
Pages: 351 - 361
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Published online: Mar 23, 2023
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