Finite Element Simulation of Freezing Technology for Borehole Stability of Gas Drilling

Abstract:

The gas drilling mainly relies on the high speed air flow to carry the cuttings. The formation water or oil mixed with the cuttings and then they stick together in clumps after the formation water or oil went into the hole annulus, the clumps stick on the drill string and the borehole. The clumps may block the hole annulus and cause the stick or bury the drill string and many other complex accident. It could stop the cuttings from sticking with the liquid through freezing the formation fluid with the liquid nitrogen. And the natural geotechnical becomes into the frozen soil, and forms the temporary solid which is intact, high strength and low-permeability. This paper utilize the ANSYS finite element program to simulate the 3D model of borehole and hole wall to calculate the freezing radius of the steady state, heat loss, temperature of the freezing point and the conductive heat time of the unsteady state. And this study has provided the basis of the freezing technology for borehole stability of gas drilling.

• Periodical: Advanced Materials Research (Volumes 962-965)
• Pages: 415-418
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.962-965.415
• Online since: June 2014
• Authors: Zong Gang Wang, Zhen Wei
• Keywords: Drilling, Finite Element, Freezing, Gas, Simulation

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