6533b86ffe1ef96bd12ce7f7

RESEARCH PRODUCT

Early-stage thermal performance design of thermo-active walls implemented in underground infrastructures

Alessio FerrariAlessio FerrariJacopo ZanninLyesse LalouiPyrène Larrey-lassalle

subject

Energy geostructuresRenewable energyFlow (psychology)0211 other engineering and technologies02 engineering and technology010502 geochemistry & geophysicsGeothermal energy01 natural sciences7. Clean energyCivil engineeringlaw.inventionlawHeat exchangerThermalLow carbon engineeringSanitary sewerComputers in Earth SciencesSafety Risk Reliability and QualityDesign methods021101 geological & geomatics engineering0105 earth and related environmental sciencesSustainable infrastructuresFlowchartUnderground infrastructuresExcavationGeotechnical Engineering and Engineering GeologyThermal potential of sitesHydrothermal modelingEnvironmental scienceEngineering design process

description

Abstract Energy geostructures (EGs) represent an innovative technology in the sustainable energy agenda and are useful for satisfying the energy needs of the built environment. They are usually involving geostructures such as piles, walls, tunnels, shafts, and sewers. The application of such technology to infrastructure projects may have considerable thermal potential because of the large surfaces that can be thermally activated. This study focuses on thermo-active walls (energy walls, EWs), which are retaining structures used to sustain the sides of excavations. Key features related to their thermal design are examined, and a design methodology is proposed. The heat-exchange modes involving EWs and the surrounding materials (concrete, soil, air) are investigated via extensive three-dimensional hydrothermal finite-element simulations involving the non-isothermal flow in the heat exchangers (HEs), as well as all other heat-exchange modes. The results are first presented as charts related to the thermal behavior of the HEs under different hydrothermal environments. Finally, a methodology for early-stage thermal performance design is proposed, and a corresponding flowchart is presented. This study may be helpful for incorporating EGs into the engineering design.

https://doi.org/10.1016/j.gete.2020.100218