COMPARATIVE ASSESSMENT OF TOTAL DRILLSTRING MOTION RESISTANCE IN A CURVED WELLBORE SECTION
DOI:
https://doi.org/10.31471/1993-9868-2026-2(46)-50-69Keywords:
вагова модель; модель без згинальної жорсткості; модель із згинальною жорсткістю; контактні реакції; замкові з’єднання; осьовий стиск.Abstract
A model with bending stiffness, which resolves the deformed axis and contact regions. Friction follows the Amontons–Coulomb law. The numerical study covers build sections with an increasing inclination from 30° to 75° and from 45° to 60°, at build rates of 5°, 10°, and 15° per 30 m. It also covers conventional and heavyweight drill pipe and three contact geometry configurations: one without tool joints, and two with a periodic tool-joint pattern in different positions. The total section length is 500 m, with equal straight extensions. Tool joints only affect the contact diameter; the joint count, average weight and bending stiffness are held constant for each pipe type. A compressive force of 5 kN is applied to the upper end, with a friction coefficient of 0.35 and a drilling fluid density of 1200 kg/m³. The study comprises 108 primary calculations and the corresponding calculations with refined numerical settings. The weight-based model underestimates total friction by 7.05–25.43% relative to the model without bending stiffness. For configurations without tool joints, the integral friction forces obtained from the models with and without bending stiffness are practically equal. With tool joints, the deviation ranges from −0.83% to +1.64% relative to the model without bending stiffness. Reconstructed contact fields for a representative configuration demonstrate that total friction values close to those of the smooth drillstring coexist with contact loss near the junctions between the straight sections and the inclination-build section, as well as the compensation of friction differences among the individual segments. With tool joints, the sign of the total deviation depends on the balance between contributions from the straight and inclination-build sections; shifting the pattern also alters the transverse boundary condition at the upper end. The model without bending stiffness may be suitable for total friction calculations when the observed deviations meet the tolerance requirements of the intended calculation. The model with bending stiffness is required for analysing deformation and local contact. These conclusions are limited to the investigated compression conditions. Configuration stability, the uniqueness of the equilibrium branch and independence from the computational domain length have not been verified
Downloads
References
1.Shi, X., & et al. (2022). Optimal design of drag reduction oscillators by considering drillstring fatigue and hydraulic loss in sliding drilling. Journal of Petroleum Science and Engineering, 208, Article 109572. https://doi.org/10.1016/j.petrol.2021.109572
2.Slabyi, O., Hrydzhuk, Y., Kondur, T., & Mokhnii, I. (2023). Simulation model of a drill string with an axial vibration generator installed. Prospecting and Development of Oil and Gas Fields, (3), 49–60. https://doi.org/10.69628/pdogf/3.2023.49
3.Slabyi, O. O., Hrydzhuk, Ya. S., Tsaruk, V. F., Kondur, T. I., & Mokhnii, I. Yu. (2024). Vyznachennia optymalnoho mistsia roztashuvannia heneratora osovykh kolyvan v burylnii koloni [Determination of the optimal placement location of the axial oscillation generator in the drill string]. Naftohazova Enerhetyka, (1(41)), 86–95. https://doi.org/10.31471/1993-9868-2024-1(41)-86-95 (in Ukrainian)
4.Johancsik, C. A., Friesen, D. B., & Dawson, R. (1984). Torque and drag in directional wells—Prediction and measurement. Journal of Petroleum Technology, 36(6), 987–992. https://doi.org/10.2118/11380-PA
5.Mason, C. J., & Chen, D. C.-K. (2007). Step changes needed to modernize T&D software. Paper presented at the SPE/IADC Drilling Conference, Amsterdam, The Netherlands. https://doi.org/10.2118/104609-MS
6.Aadnoy, B. S., Fazaelizadeh, M., & Hareland, G. (2010). A 3D analytical model for wellbore friction. Journal of Canadian Petroleum Technology, 49(10), 25–36. https://doi.org/10.2118/141515-PA
7.Bembenek, M., & et al. (2024). An analytical–numerical model for determining “drill string–wellbore” frictional interaction forces. Energies, 17(2), Article 301. https://doi.org/10.3390/en17020301
8.Mitchell, R. F., & Samuel, R. (2009). How good is the torque/drag model? SPE Drilling & Completion, 24(1), 62–71. https://doi.org/10.2118/105068-PA
9.Mirhaj, S. A., Kaarstad, E., & Aadnoy, B. S. (2016). Torque and drag modeling; Soft-string versus stiff-string models. Paper presented at the SPE/IADC Middle East Drilling Technology Conference and Exhibition, Abu Dhabi, UAE. https://doi.org/10.2118/178197-MS
10. Rocheleau, D. N., & Dareing, D. W. (1992). Effect of drag forces on bit weight in high-curvature well bores. Journal of Energy Resources Technology, 114(3), 175–180. https://doi.org/10.1115/1.2905938
11.Mayouf, M., & Hadjadj, A. (2022). A stiff-string model for torque and drag analysis in directional wells. Arabian Journal for Science and Engineering, 47(9), 12089–12102. https://doi.org/10.1007/s13369-022-06881-8
12.Yang, D., Rahman, M. K., & Chen, Y. (2008). Bottomhole assembly analysis by finite difference differential method. International Journal for Numerical Methods in Engineering, 74(9), 1495–1517. https://doi.org/10.1002/nme.2221
13.Arbatani, S., & et al. (2016). An approach to directional drilling simulation: Finite element and finite segment methods with contact. Computational Mechanics, 57(6), 1001–1015. https://doi.org/10.1007/s00466-016-1274-2
14.Yang, C., & et al. (2021). A highly efficient beam-in-beam large sliding contact method for flexible multibody dynamics. Computational Mechanics, 67(4), 1155–1175. https://doi.org/10.1007/s00466-021-01984-9
15.Goicoechea, H. E., Buezas, F. S., & Rosales, M. B. (2019). A non-linear Cosserat rod model for drill-string dynamics in arbitrary borehole geometries with contact and friction. International Journal of Mechanical Sciences, 157–158, 98–110. https://doi.org/10.1016/j.ijmecsci.2019.04.023
16.Zhu, X., & et al. (2015). New analysis theory and method for drag and torque based on full-hole system dynamics in highly deviated well. Mathematical Problems in Engineering, 2015, Article 535830. https://doi.org/10.1155/2015/535830
17.Tengesdal, N. K., Fotland, G., Holden, C., & Haugen, B. (2023). Modeling of drill string dynamics in directional wells for real-time simulation. SIMULATION, 99(12), 1235–1248. https://doi.org/10.1177/00375497231175927
18.Mahjoub, M., Dao, N.-H., & Menand, S. (2019). Modeling the effect of axial oscillation tools in torque and drag computations. Paper presented at the SPE/IADC International Drilling Conference and Exhibition, The Hague, The Netherlands. https://doi.org/10.2118/194133-MS
19.Miska, S. Z., & et al. (2015). Dynamic soft string model and its practical application. Paper presented at the SPE/IADC Drilling Conference and Exhibition, London, England, UK. https://doi.org/10.2118/173084-MS
20.Samuel, R., & Huang, W. (2020). Dynamic torque and drag model. Paper presented at the SPE Annual Technical Conference and Exhibition, Virtual. https://doi.org/10.2118/201629-MS
21.Liyanarachchi, S., & Rideout, G. (2024). Improved stiff string torque and drag prediction using a computationally efficient contact algorithm. Mathematical and Computer Modelling of Dynamical Systems, 30(1), 417–443. https://doi.org/10.1080/13873954.2024.2348152
Downloads
Published
How to Cite
Issue
Section
License
Copyright (c) 2026 Oil and Gas Power Engineering
This work is licensed under a Creative Commons Attribution-ShareAlike 4.0 International License.
.png)
1.png){kind=logo}
