Thermo‐Pile: A Numerical Tool for the Design of Energy Piles

Mimouni, Thomas; Laloui, Lyesse

doi:10.1002/9781118761809.ch13

Cited by 4 publications

(3 citation statements)

References 11 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The use of a one-dimensional (1D) thermomechanical analysis of energy piles has been proven to be a sufficient technique (Knellwolf et al, 2011;Mimouni and Laloui, 2013). However, the use of 1D analyses to assess the thermomechanical behaviour of energy piles lacks the ability to account for the effect of varying thermal loads; rather, it enforces a uniform temperature change over the entire pile.…”

Section: Finite-element Modelling Approachmentioning

confidence: 99%

Non-uniform thermal strains and stresses in energy piles

AbdelazizSherif

Ozudogru

2016

Environmental Geotechnics

View full text Add to dashboard Cite

2This paper presents the non-uniform thermally induced strains and stresses that develop in the cross-sections of energy piles when subjected to operational energy demands. The thermal operation of energy piles depends on the thermal demands of the supported building. These thermal demands vary seasonally, daily and even hourly, which generates non-uniform temperature changes over the pile's cross-section throughout the lifetime of the system. Therefore, non-uniform thermal strains and stresses develop over the cross-section of energy piles. Numerical analyses performed in this study indicate that the maximum temperature changes and the thermally induced strains and stresses occur near the location of the ground loops. Further, contradicting the current understanding that heating the piles creates only thermal compressive stresses, while cooling them creates only thermal tensile stresses;tensile and compressive thermal stresses were found to coexist during heating and cooling over the same pile crosssection due to the non-uniform temperature changes. Furthermore, the magnitude of the tensile stresses that develop due to non-uniform temperature changes is crucial when the reinforcing cage is cut short of the pile toe.Finally, ignoring the non-uniform temperature changes while processing the temperatures and strains measured in full-scale tests will result in errors in approximated thermal stresses.

show abstract

Section: Finite-element Modelling Approachmentioning

confidence: 99%

Non-uniform thermal strains and stresses in energy piles

AbdelazizSherif

Ozudogru

2016

Environmental Geotechnics

View full text Add to dashboard Cite

show abstract

“…Knellwolf et al [26] developed the Thermo-Pile software (see Section 9) [152], which uses a load transfer approach. The software was coupled with thermal response analysis and verified by back-analysis of two well documented experimental tests-real scale energy piles at Swiss Federal Institute of Technology in Lausanne [153] and Lambeth College in London [154].…”

Section: Thermo-mechanical Interactions and Constitutive Modelingmentioning

confidence: 99%

“…The basic general characteristics of the most common tools, including type of a model and referencing applications, are shown in the Table 1. 1D finite differences in radial direction; size of the piles; no water transfer taken into account; mesh analysis; studies THM effects [152,228,229] (validation and case study)…”

Section: Software Toolsmentioning

confidence: 99%

Reviewing the Modeling Aspects and Practices of Shallow Geothermal Energy Systems

et al. 2020

View full text Add to dashboard Cite

Shallow geothermal energy systems (SGES) may take different forms and have recently taken considerable attention due to energy geo-structures (EGS) resulting from the integration of heat exchange elements in geotechnical structures. Still, there is a lack of systematic design guidelines of SGES. Hence, in order to contribute towards that direction, the current study aims at reviewing the available SGES modeling options along with their various aspects and practices. This is done by first presenting the main analytical and numerical models and methods related to the thermal behavior of SGES. Then, the most important supplementary factors affecting such modeling are discussed. These include: (i) the boundary conditions, in the form of temperature variation or heat flow, that majorly affect the predicted thermal behavior of SGES; (ii) the spatial dimensions that may be crucial when relaxing the infinite length assumption for short heat exchangers such as energy piles (EP); (iii) the determination of SGES parameters that may need employing specific techniques to overcome practical difficulties; (iv) a short-term vs. long-term analysis depending on the thermal storage characteristics of GHE of different sizes; (v) the influence of groundwater that can have a moderating effect on fluid temperatures in both heating and cooling modes. Subsequently, thermo-mechanical interactions modeling issues are addressed that may be crucial in EGS that exhibit a dual functioning of heat exchangers and structural elements. Finally, a quite lengthy overview of the main software tools related to thermal and thermo-hydro-mechanical analysis of SGES that may be useful for practical applications is given. A unified software package incorporating all related features of all SGES may be a future aim.

show abstract

Cyclic Thermo-Mechanical Analysis of Energy Piles in Sand

Saggu

Chakraborty

2014

Geotech Geol Eng

View full text Add to dashboard Cite

Thermo‐Pile: A Numerical Tool for the Design of Energy Piles

Cited by 4 publications

References 11 publications

Non-uniform thermal strains and stresses in energy piles

Non-uniform thermal strains and stresses in energy piles

Reviewing the Modeling Aspects and Practices of Shallow Geothermal Energy Systems

Cyclic Thermo-Mechanical Analysis of Energy Piles in Sand

Contact Info

Product

Resources

About