Field experiments to evaluate thermal performance of energy slabs with different installation conditions

Seokjae Lee, Sangwoo Park, Minkyu Kang, Hangseok Choi

Research output: Contribution to journalArticle

1 Citation (Scopus)

Abstract

The energy slab is a novel type of horizontal Ground Heat Exchanger (GHEX), where heat exchange pipes are encased in building slab structures. The thermal performance of energy slabs is usually inferior to the conventional closed-loop vertical GHEX because its installation depth is relatively shallow and therefore affected by ambient air temperature. In this paper, heat exchange pipes were made of not only conventional high-density polyethylene (HDPE), but also stainless steel (STS), which is expected to enhance the thermal performance of the energy slabs. In addition to a floor slab, a side wall slab was also used as a component of energy slabs to maximize the use of geothermal energy that can be generated from the underground space. Moreover, a thermal insulation layer in the energy slabs was considered in order to reduce thermal interference induced by ambient air temperature. Consequently, two different field-scale energy slabs (i.e., floor-type and wall-type energy slabs) were constructed in a test bed, and two types of heat exchange pipes (i.e., STS pipe and HDPE pipes) were installed in each energy slab. A series of thermal response tests (TRTs) and thermal performance tests (TPTs) were conducted to evaluate the heat exchange performance of the constructed energy slabs. Use of the STS heat exchange pipe enhanced the thermal performance of energy slabs. Additionally, the wall-type energy slab had a similar thermal performance to the floor-type energy slab, which infers the applicability of the additional use of the wall-type energy slab. Note that if an energy slab is not thermally cut off from the building's interior space with the aid of thermal insulation layers, heat exchange within the energy slabs should be significantly influenced by fluctuations in ambient temperature.

Original languageEnglish
Article number2214
JournalApplied Sciences (Switzerland)
Volume8
Issue number11
DOIs
Publication statusPublished - 2018 Nov 10

Fingerprint

installing
slabs
Experiments
energy
Pipe
Stainless Steel
heat
Stainless steel
Thermal insulation
Polyethylene
High density polyethylenes
Hot Temperature
stainless steels
thermal insulation
Heat exchangers
heat exchangers
Interiors (building)
polyethylenes
Geothermal energy
Steel pipe

Keywords

  • Energy slab
  • Ground heat exchanger
  • Thermal Performance Test
  • Thermal Response Test
  • Underground structure

ASJC Scopus subject areas

  • Materials Science(all)
  • Instrumentation
  • Engineering(all)
  • Process Chemistry and Technology
  • Computer Science Applications
  • Fluid Flow and Transfer Processes

Cite this

Field experiments to evaluate thermal performance of energy slabs with different installation conditions. / Lee, Seokjae; Park, Sangwoo; Kang, Minkyu; Choi, Hangseok.

In: Applied Sciences (Switzerland), Vol. 8, No. 11, 2214, 10.11.2018.

Research output: Contribution to journalArticle

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