Laboratory experimental and numerical thermal response tests in thermal piles prototypes in tropical soil

Abstract

This paper provides preliminary results on geothermal energy piles (GEPs) for the thermal climatization of structures founded on the typical tropical unsaturated soil of the central region of Brazil. The research employed a series of prototype simulations of a thermal pile embedded into a calibration chamber with compacted unsaturated soil. It closely simulates the behavior of a (prototype) section from real scale GEPs founded in the geotechnical media of the region, in terms of compactness, mineralogy, water content and thermal variables. One of the on-going thermal tests was numerically simulated with a Multiphysics commercial software to calibrate a model and expand the results to possible scenarios of distinct (laboratory) GEP performance. The analyses will base future simulations of typical foundation layouts for large-scale structures founded on tropical soils of the region to verify the thermal energy efficiency under average operational conditions. Besides the known limitations of this research, still at early stage, an initial assessment was achieved to design shallow geothermal systems for local conditions.