68th Canadian Geotechnical Conference and 7th Canadian Permafrost Conference

A NUMERICAL STUDY OF THE INFLUENCE OF GROUNDWATER FLOW ON HEAT LOSS FROM RESIDENTIAL FOUNDATIONS

Session: Groundwater / Eaux souterraines

Dominique Beaulieu, Université Laval (Canada)
Jean Côté, Université Laval (Canada)

This paper aims at determining the relative effects of groundwater flow (heat convection) on the total heat loss towards surrounding soils using a finite elements method to solve coupled heat and mass transfer in porous media. Three different soils were studied: clay, silt and sand. The results show that the flow of groundwater under the foundation has a significant influence on the total foundation heat loss if the surrounding soil is made of coarse grained soil such as pervious sands. As expected, the high water conductivity of sand has a strong influence on total heat loss due to varying pore-water velocities (hydraulic gradient). On the other hand, the results also show that low permeability soils such as silts and clays have insignificant influence on the total heat loss. Very low pore-water velocity does not allow for noticeable heat extraction under any water table or hydraulic gradients conditions.