Three-Dimensional Numerical Study of DTH Bit-Rock Interaction with HPWJ Downhole Slotting: Influence of Bit Design and Bottom Hole Geometric Conditions on Rock Breaking Efficiency in Percussive Drilling
Résumé
In the context of the EU project H2020 ORCHYD aiming at increasing hard rock drilling rate in deep geothermal wells, 3D finite element simulations of bit-rock interactions were performed to assess how by combining High Pressure Water Jetting (HPWJ)-made groove and bottom-hole geometry can contribute to improve the down-hole percussive performance. Twelve different groove depthbottom-hole configurations were investigated. A Red Bohus granite rock was modelled using a continuum, plasticity-based, damage model calibrated using uniaxial and triaxial experimental test data. The presence of the groove affects both impact load and penetration. The groove also affects the amount and extent of damage around and between indents, especially near the groove, as well as the total volume fractured, or removed. It is finally found that the presence of a groove is significantly beneficial only for some specific bit profiles.
Domaines
Sciences de l'ingénieur [physics]
Fichier principal
Three-Dimensional Numerical Study of DTH Bit–Rock Interaction with HPWJ Downhole.pdf (972.03 Ko)
Télécharger le fichier
Origine | Fichiers produits par l'(les) auteur(s) |
---|