Experimental Hydration Temperature Increase in Borehole Heat Exchangers during Thermal Response Tests for Geothermal Heat Pump Design

Fabio Minchio, Gabriele Cesari, Claudio Pastore and Marco Fossa
Additional contact information
Fabio Minchio: Studio 3F Engineering, Via IV Novembre 14, 36051 Creazzo, Italy
Gabriele Cesari: Geo-Net S.r.l., Via Giuseppe Saragat 5, 40026 Imola, Italy
Claudio Pastore: Geo-Net S.r.l., Via Giuseppe Saragat 5, 40026 Imola, Italy
Marco Fossa: DIME Department of Mechanical, Energy, Management and Transportation Engineering, the University of Genova, Via Opera Pia 15a, 16145 Genova, Italy

Energies, 2020, vol. 13, issue 13, 1-16

Abstract: The correct design of a system of borehole heat exchangers (BHEs) is the primary requirement for attaining high performance with geothermal heat pumps. The design procedure is based on a reliable estimate of ground thermal properties, which can be assessed by a Thermal Response Test (TRT). The TRT analysis is usually performed adopting the Infinite Line Source model and is based on a series of assumptions to which the experiment must comply, including stable initial ground temperatures and a constant heat transfer rate during the experiment. The present paper novelty is related to depth distributed temperature measurements in a series of TRT experiments. The approach is based on the use of special submersible sensors able to record their position inside the pipes. The focus is on the early period of BHE installation, when the grout cement filling the BHE is still chemically reacting, thus releasing extra heat. The comprehensive dataset presented here shows how grout hydration can affect the depth profile of the undisturbed ground temperature and how the temperature evolution in time and space can be used for assessing the correct recovery period for starting the TRT experiment and inferring information on grouting defects along the BHE depth.

Keywords: ground coupled heat pumps; borehole heat exchangers; distributed temperature response test; grouting material; hydration heat release (search for similar items in EconPapers)
JEL-codes: Q Q0 Q4 Q40 Q41 Q42 Q43 Q47 Q48 Q49 (search for similar items in EconPapers)
Date: 2020
References: View references in EconPapers View complete reference list from CitEc
Citations: View citations in EconPapers (1)

Downloads: (external link)
https://www.mdpi.com/1996-1073/13/13/3461/pdf (application/pdf)
https://www.mdpi.com/1996-1073/13/13/3461/ (text/html)

Related works:
This item may be available elsewhere in EconPapers: Search for items with the same title.

Export reference: BibTeX RIS (EndNote, ProCite, RefMan) HTML/Text

Persistent link: https://EconPapers.repec.org/RePEc:gam:jeners:v:13:y:2020:i:13:p:3461-:d:380283

Access Statistics for this article

Energies is currently edited by Ms. Agatha Cao

More articles in Energies from MDPI
Bibliographic data for series maintained by MDPI Indexing Manager ().