A Study on Force Situation of the Coring Pipe Caused by Filling Lunar Regolith in the Drilling Process

Abstract:

To find out the influence factors to the force situation of the coring pipe in the drilling process, the discrete element method is employed to build the lunar regolith model and simulate the interaction between soil and the drill. A viscoelastic contact model is introduced to represent the impact between particles. To make sure the validity of the model, a biaxial-test is conducted to optimize the micro-parameters of the model. The drilling process is simplified to an inserted process and the model after calibration is in use. From the computational simulation results, conclusions can be made: to reduce the drilling speed or to drill aslant may be good to decrease the force loaded on the inside wall. Enlargement of the diameter and thickness can improve the sampling efficiency and prevent the soil sample from being destroyed, and drilling aslant may be harmful to the sample.

• Periodical: Applied Mechanics and Materials (Volume 577)
• Pages: 267-272
• DOI: https://doi.org/10.4028/www.scientific.net/AMM.577.267
• Online since: July 2014
• Authors: Tian Xi Liu*, Cheng Wei, Liang Ma, Yang Zhao
• Keywords: Biaxial Test, Discrete Element Method, Insertion Process, Simplified Movement, Viscoelastic Contact Model

References

[1] Cundall, P.A.; Strack, O.D.L.: A discrete numerical model for granular assemblies. Geotechnique, Vol. 29, pp.47-65. (1979).

DOI: 10.1680/geot.1979.29.1.47

[2] Donzé, F.V.; Richefeu, V.; Magnier, S.A.: Advances in discrete element method applied to soil, rock and concrete mechanics. State of the art of geotechnical engineering. Electronic Journal of Geotechnical Engineering, Vol. 8, pp.1-44, (2009).

[3] Zhao, C.: Computational simulation of frictional drill-bit movement in cemented granular materials. Finite Elements in Analysis and Design, Vol. 47, No. 8, pp.877-885, (2011).

DOI: 10.1016/j.finel.2011.03.003

[4] Mpagazehe, J.N.; Queiruga, A.F.; Higgs. III, C.F.: Towards an understanding of the drilling process for fossil fuel energy: A continuum-discrete approach. Tribology International, Vol. 59, pp.273-283, (2013).

DOI: 10.1016/j.triboint.2012.08.001

[5] Jiang, M.J.; Yu, H. -S.; Harris, D.: A novel discrete model for granular material incorporating rolling resistance. Computers and Geotechnics, Vol. 32, p.340–357, (2005).

DOI: 10.1016/j.compgeo.2005.05.001

[6] Gromov, V.: Physical and Mechanical Properties of Lunar and Planetary Soils. Earth Moon and Planets, Vol. 80, No. 1, pp.51-72, (1998).