Scaling laws for the modelling of energy geostructures

Abstract

Among the different solutions to meet the increasing need for renewable energies, energy geostructures, and particularly energy piles, are very promising. However, their dual role (structural support and energy harvester) raises design questions and safety issues. In addition, they are often placed within a groundwater flow and the influence of seepage on thermal loadings and mechanical response is still to be characterised. In this perspective, centrifuge modelling can play a significant role as in lots of geotechnical problems. In the present case, reduced scale models present a supplementary advantage since diffusion timescales are highly reduced. Scaling factor for time is 1/N2 if scaling factor for lengths is 1/N. Nevertheless, the numerous phenomena to consider make it difficult to ensure the similarity between model and prototype. This paper derives and collates all the scaling laws and important points to be aware of when centrifuge modelling energy piles.