Underground electric cables a correct evaluation of the soil thermal resistance

Thanks to an experimental system, some useful data were collected for the validation of a 2D FEM model of an excavated area with a linear heat source reproducing the underground conduit. The numerical model presents a variation of both the geometrical parameters of the excavated area and the distance characterizing other cables (hence heat sources) located in the same site of installation examined. In this way two dimensionless coefficients, useful to correct the values of the thermal resistance furnished by the current regulations, were determined.