Thermal behaviour of geothermal diaphragm walls: Evaluation of exchanged thermal power

Abstract Geothermal structures represent an alternative source for heating and cooling of constructions. They are being widely used for their great potential in providing clean energy. The thermal performance of geothermal structures can be evaluated by measuring the possible exchanged heat. However, the assessment of the allowable exchanged heat is a complex issue which depends on several factors and is considered as an indicator of the efficiency and sustainability of these structures. This paper presents a new generalized sophisticated approach for the assessment of the possible exchanged power between geothermal diaphragm walls and the surrounding soil. The impacts of groundwater flow, active length of the diaphragm wall, and type of thermal load; on the thermal performance of geothermal diaphragm walls, are studied in details. Results obtained show that the presence of significant groundwater flow and activating the whole length of diaphragm wall, both affect positively the thermal exchange. Moreover, the type of the considered thermal load is found to have a direct impact on the thermal performance of diaphragm walls.