THERMAL SCIENCE

International Scientific Journal

Marija M Vasilev

,

Miloš J BanjacORCID

THERMAL RECOVERY TEST FOR DETERMINING THE THERMAL CONDUCTIVITY OF THE SOIL

ABSTRACT
This paper presents a new in-situ experimental procedure for determining a thermal conductivity of soil, as one of the thermophysical properties necessary for dimensioning vertical buried heat exchangers of geothermal heat pumps. The proposed method, called the thermal recovery test, is based on the assumption that there is a direct analogy between the hydrodynamic process of filling (recovery) the well with water from a porous aquifer after its partial or complete discharging and the process of establishment of thermal equilibrium in an infinite medium previously disturbed by a line heat sink (source). Apart from presentation the theoretical background of these two phenomena, the display of the identical theoretical logarithmic character of the change of hydrostatic pressure and soil temperature, description of the experimental procedure, the experimental results of three performed experiments are also presented. Additionally, results for the experimentally obtained values of the thermal conductivity of the soil are compared with those obtained from the thermal response test, and the advantages and drawbacks of the new thermal recovery test method are analyzed.
KEYWORDS
thermal conductivity of soil, vertical buried heat exchangers, thermal response test, Thermal Recovery Test
PAPER SUBMITTED: 2023-08-25
PAPER REVISED: 2023-09-28
PAPER ACCEPTED: 2023-10-13
PUBLISHED ONLINE: 2023-10-15
DOI REFERENCE: https://doi.org/10.2298/TSCI230825223V
CITATION EXPORT: view in browser or download as text file
THERMAL SCIENCE YEAR 2024, VOLUME 28, ISSUE No. 1, PAGES [425 - 435]
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Thermal recovery test for determining the thermal conductivity of the soil

© 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