Effect of Ground Mineralogy on Energy Pile Performance in Dense Sand

Abstract:

Geothermal energy piles have emerged as a cost effective and efficient solution for heating and cooling buildings through renewable energy. Although significant research effort has been dedicated to investigating the performance of these systems, the effect of ground mineralogy has received little attention. This study examines the likely performance of energy piles in dense sand with varying mineralogy. A 3D thermal discrete element model is used to determine the dry thermal conductivity of quartz, feldspar and mica rich sand. This is then used in a 2D finite element analysis to estimate the dissipation/extraction capacity of the soil surrounding a typical energy pile. A 35% increase in quartz content is predicted to result in 51% improvement in the thermal performance of a pile.

• Periodical: Applied Mechanics and Materials (Volume 846)
• Pages: 325-330
• DOI: https://doi.org/10.4028/www.scientific.net/AMM.846.325
• Online since: July 2016
• Authors: Abraham Kazzaz*, Itai Einav, Gwénaëlle Proust, Yi Xiang Gan
• Keywords: Dense Sand, Discrete Element, Energy Pile, Mineralogy, Thermal Conductivity

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