Laboratory thermal conductivity measurements on gravel sample = Misure di laboratorio della conducibilità termica su campioni di ghiaia

Modern Ground Source Heat Pumps (GSHPs) systems must be designed by taking into account the ground thermal properties, in order to properly plan the capability of the heat pumps to transfer calories through the Ground Source Heat Exchangers (GSHE) to the subsoil (and vice versa). As a result, in order to properly plan the best fitting Heating, Ventilation and Air Conditioning (HVAC) systems, designers need to couple the energy building loads requirements to the ground thermal properties. Usually, some available information about the geological stratigraphy around the GSHE and soils’ thermal properties bibliography data could provide the preliminary estimation of the main parameters to proper design the GSHP with the related GSHE. On the other hands, alluvial plains and valley floors usually host most of the urban areas and anthropic activities such as cities, commercial districts and industrial region. As a result, for HVAC applications, thermal properties of alluvial materials should be studied more in detail since they have quite a considerable impact on the HVAC efficiency. Gravel thermal properties have been detected by the means of a guarded hot plate Taurus Instruments TLP 800, where some changes in the setup have been made in order to finalize the thermal measurements.