Simulating fragmentation of hard granitic rocks during electropulse drilling

Daniel Vogler, Stuart D Walsh, Martin O Saar

Research output: Contribution to conferenceAbstract

Abstract

Drilling in hard rock constitutes a significant portion of the total cost associated with geothermal power plant operation. Conventional rotary-head drilling, however, is commonly associated with frequent equipment damage, leading to high drilling costs. Contact-less drilling technologies, such as electropulse drilling, are therefore being developed to improve drilling efficiency. Electropulse drilling uses repeated application of high-voltage pulses to fragment the rock mass. During each drilling pulse, the electric potential applied on the drill bit discharges through the solid rock mass. While experiments show the rupturing of the rock mass occurring during discharge, the physical processes leading to this rock damage are still poorly understood. We present a model for the coupled electro-mechanical processes responsible for rock fragmentation. Simulated are the passage of the pulse through the rock mass, electrical breakdown, and the mechanical behaviour on the grain scale. Different factors, such as rock composition, pulse duration and maximum applied voltage are considered. The presented model deepens understanding of the different electro-mechanical and operational factors required for successful electropulse drilling.
Original languageEnglish
Number of pages1
Publication statusPublished - 2019
EventFall Meeting of the American-Geophysical-Union 2019 - San Francisco, United States of America
Duration: 9 Dec 201913 Dec 2019
https://www.agu.org/fall-meeting

Conference

ConferenceFall Meeting of the American-Geophysical-Union 2019
Abbreviated titleAGU 2019
CountryUnited States of America
CitySan Francisco
Period9/12/1913/12/19
Internet address

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