Distributed Thermal Response Test on a U-Pipe Borehole Heat Exchanger
2009 (English)In: Proc. Effstock 2009, 11th International Conference on Thermal Energy Storage, Stockholm, Sweden: Academic Conferences Publishing, 2009Conference paper (Refereed)
In a Distributed Thermal Response Test (DTRT) the ground thermal conductivity and boreholethermal resistance are determined at many instances along the borehole. Here, such a testis carried out at a 260 m deep water filled energy well, equipped with a U-pipe borehole heatexchanger, containing an aqueous solution of ethanol as working fluid. Distributed temperaturemeasurements are carried out using fiber optic cables placed inside the U-pipe, duringfour test phases: undisturbed ground conditions, fluid pre-circulation, constant heat injection,and borehole recovery. A line source model is used for simulating the borehole thermal response.Fluid temperature profiles during the test are presented. The results show local variationsof the ground thermal conductivity and borehole thermal resistance along the boreholedepth, as well as a deviation of the latter as compared to the one resulting from a standardthermal response test.
Place, publisher, year, edition, pages
Stockholm, Sweden: Academic Conferences Publishing, 2009.
IdentifiersURN: urn:nbn:se:kth:diva-81315OAI: oai:DiVA.org:kth-81315DiVA: diva2:497303
Effstock 2009, 11th International Conference on Thermal Energy Storage, Stockholm, June 14-17 2009
QC 201205022012-02-102012-02-102013-02-04Bibliographically approved