

- How to add rayleigh damping ratio to mohr coulomb flac3d update#
- How to add rayleigh damping ratio to mohr coulomb flac3d full#
The tool can simulate cuttings movement at particle scale under laminar or turbulent fluid flow conditions and evaluate the efficiency of cutting removal. For cuttings transport in annulus, a 3D numerical particle flowing model has been developed with aid of analytical approaches. From the model, Rate of Penetration (ROP) and rock failure history can be estimated.
How to add rayleigh damping ratio to mohr coulomb flac3d update#
Besides multiple failure criteria, the tool also includes a damping algorithm to dissipate oscillation energy more » and a fatigue/damage algorithm to update rock properties during each impact. For rock mechanics modeling, a dynamic numerical tool has been developed to describe rock damage and failure, including rock crushing by compressive bit load, rock fracturing by both shearing and tensile forces, and rock weakening by repetitive compression-tension loading. Both analytical and numerical approaches are deployed to investigate drilling processes such as drillbit penetration with compression, rotation and percussion, rock response with stress propagation, damage accumulation and failure, and debris transportation inside the annulus after disintegrated from rock. Based on the current understandings, a conceptual drilling model is proposed for modeling efforts.

Literature reviews document the history, pros and cons, and rock failure physics of percussion drilling in oil and gas industries.
How to add rayleigh damping ratio to mohr coulomb flac3d full#
The project has been divided into multiple tasks: literature reviews, analytical and numerical modeling, full scale laboratory testing and model validation, and final report delivery.

This report summarizes the research efforts on the DOE supported research project Percussion Drilling (DE-FC26-03NT41999), which is to significantly advance the fundamental understandings of the physical mechanisms involved in combined percussion and rotary drilling, and thereby facilitate more efficient and lower cost drilling and exploration of hard-rock reservoirs.
