Long-Term Thermal Performance of Group of Energy Piles in Unsaturated Soils under Cyclic Thermal Loading
Geothermal energy piles (GEPs) are an environmentally friendly heat exchange technology that dualizes the role of the structural foundation pile for load support and in meeting the building heating/cooling need. Energy loops made from high-density polyethylene, which allow heat carrier fluid circula...
| Main Authors: | , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
MDPI AG
2021-07-01
|
| Series: | Energies |
| Subjects: | |
| Online Access: | https://www.mdpi.com/1996-1073/14/14/4122 |
| _version_ | 1797527221392375808 |
|---|---|
| author | Abubakar Kawuwa Sani Rao Martand Singh |
| author_facet | Abubakar Kawuwa Sani Rao Martand Singh |
| author_sort | Abubakar Kawuwa Sani |
| collection | DOAJ |
| description | Geothermal energy piles (GEPs) are an environmentally friendly heat exchange technology that dualizes the role of the structural foundation pile for load support and in meeting the building heating/cooling need. Energy loops made from high-density polyethylene, which allow heat carrier fluid circulation, are fitted into the pile foundation elements to extract or inject and store heat energy in the soil surrounding the pile. This paper reports the results of a numerical study investigating the long-term behaviour of a group of energy piles embedded in unsaturated soils (sand and clay) under continuous cyclic heating and cooling load. Additionally, two scenarios were investigated where: (1) the whole GEPs were heated and cooled collectively; (2) alternate piles were heated and cooled. It was found that the trend of temperature magnitude at all the observed locations decreases with time as a result of the continuous heating and cooling cycles. Furthermore, subjecting alternate GEPs to the heating and cooling cycles result in lower temperature development in comparison to thermally activating all the GEPs in the group. This is attributed to the applied thermal load, which is 0.5 times that considered in the first case. However, this might not be the case where equal thermal load is applied on the GEPs in the two cases investigated. |
| first_indexed | 2024-03-10T09:40:55Z |
| format | Article |
| id | doaj.art-34f56fdc9feb46f6bc589f529d9fd223 |
| institution | Directory Open Access Journal |
| issn | 1996-1073 |
| language | English |
| last_indexed | 2024-03-10T09:40:55Z |
| publishDate | 2021-07-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Energies |
| spelling | doaj.art-34f56fdc9feb46f6bc589f529d9fd2232023-11-22T03:40:24ZengMDPI AGEnergies1996-10732021-07-011414412210.3390/en14144122Long-Term Thermal Performance of Group of Energy Piles in Unsaturated Soils under Cyclic Thermal LoadingAbubakar Kawuwa Sani0Rao Martand Singh1Department of Civil and Environmental Engineering, Faculty of Engineering and Physical Sciences, University of Surrey, Guildford GU2 7XH, UKDepartment of Civil and Environmental Engineering, Norwegian University of Science & Technology, (NTNU), 7034 Trondheim, NorwayGeothermal energy piles (GEPs) are an environmentally friendly heat exchange technology that dualizes the role of the structural foundation pile for load support and in meeting the building heating/cooling need. Energy loops made from high-density polyethylene, which allow heat carrier fluid circulation, are fitted into the pile foundation elements to extract or inject and store heat energy in the soil surrounding the pile. This paper reports the results of a numerical study investigating the long-term behaviour of a group of energy piles embedded in unsaturated soils (sand and clay) under continuous cyclic heating and cooling load. Additionally, two scenarios were investigated where: (1) the whole GEPs were heated and cooled collectively; (2) alternate piles were heated and cooled. It was found that the trend of temperature magnitude at all the observed locations decreases with time as a result of the continuous heating and cooling cycles. Furthermore, subjecting alternate GEPs to the heating and cooling cycles result in lower temperature development in comparison to thermally activating all the GEPs in the group. This is attributed to the applied thermal load, which is 0.5 times that considered in the first case. However, this might not be the case where equal thermal load is applied on the GEPs in the two cases investigated.https://www.mdpi.com/1996-1073/14/14/4122ground heat exchangerheat fluxnumerical modellingunsaturated soilsenergy pile grouplong-term performance |
| spellingShingle | Abubakar Kawuwa Sani Rao Martand Singh Long-Term Thermal Performance of Group of Energy Piles in Unsaturated Soils under Cyclic Thermal Loading Energies ground heat exchanger heat flux numerical modelling unsaturated soils energy pile group long-term performance |
| title | Long-Term Thermal Performance of Group of Energy Piles in Unsaturated Soils under Cyclic Thermal Loading |
| title_full | Long-Term Thermal Performance of Group of Energy Piles in Unsaturated Soils under Cyclic Thermal Loading |
| title_fullStr | Long-Term Thermal Performance of Group of Energy Piles in Unsaturated Soils under Cyclic Thermal Loading |
| title_full_unstemmed | Long-Term Thermal Performance of Group of Energy Piles in Unsaturated Soils under Cyclic Thermal Loading |
| title_short | Long-Term Thermal Performance of Group of Energy Piles in Unsaturated Soils under Cyclic Thermal Loading |
| title_sort | long term thermal performance of group of energy piles in unsaturated soils under cyclic thermal loading |
| topic | ground heat exchanger heat flux numerical modelling unsaturated soils energy pile group long-term performance |
| url | https://www.mdpi.com/1996-1073/14/14/4122 |
| work_keys_str_mv | AT abubakarkawuwasani longtermthermalperformanceofgroupofenergypilesinunsaturatedsoilsundercyclicthermalloading AT raomartandsingh longtermthermalperformanceofgroupofenergypilesinunsaturatedsoilsundercyclicthermalloading |