Науковий вісник НГУ

Computer simulation of fluid mechanics and heat transfer processes at the working face of borehole rock

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Category: Mining

Last Updated on 18 November 2016

Published on 17 November 2016

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Authors:

A.Yu.Dreus, Cand. Sc. (Tech.), Assoc. Prof., Oles Honchar Dnipropetrovsk National University, Dnipro, Ukraine, e-mail: This email address is being protected from spambots. You need JavaScript enabled to view it.

K.Ye.Lysenko, Cand. Sc. (Tech.), Oles Honchar Dnipropetrovsk National University, Dnipro, Ukraine, e-mail: This email address is being protected from spambots. You need JavaScript enabled to view it.

Abstract:

Purpose. The numerical study of the drill mud flow speeds field at the working face of a borehole. Substantiation of methodology to calculate the convection heat transfer rates on the surface of a diamond core bit during its cooling.

Methodology. Computational fluid dynamics methods (CFD modeling) were used in the course of the study.

Findings. The physical and mathematical models of fluid mechanics and heat transfer processes at the working face of a borehole during its boring with diamond core bits are suggested herein. The field of circulating drill mud flow speeds around the diamond core bit at the drilling of rock formation was obtained. Regarding the convective heat exchange, the computer simulation demonstrated that a notable change of flow speed field during the boring occurs throughout the height of the bit. In the course of the bit rotation the flow speed field can be considered uniform alongside the azimuthal direction. The ultimate non-uniformity of the speed field is revealed in the water hole passages of the drilling core bit, which results in its heavier wear. Based on the distribution speed calculation results, the convection heat transfer coefficients were defined throughout the height of the drilling core bit. The study revealed that, owing to significant acceleration of the flow, the most intense heat exchange processes took place in the waterhole passages.

Originality. The theory of fluid mechanics processes at the working face of a borehole during the boring was further developed. New data were obtained on the distribution of the flow speed field and pressure field in the circulating fluid at the bottom-hole area. The non-uniform nature of the fields was demonstrated herein. It is shown that, due to the locally uniform field of speeds distribution, it is possible to assume that the bit convection heat exchange ratios are constant in the certain areas.

Practical value. The outcomes of the fluid mechanics field modeling can be used for determination of the optimum sizes and shapes of the waterhole passages in the course of designing new boring tools and equipment. The obtained heat exchange ratios enable to carry out calculations of temperature fields in the crown bit body, which is necessary to establish the resource and power saving modes of drilling.

References/Список літератури

1. Kozhevnikov, A. A., Filimonenko, N. V., and Zhikaliak, N. V., 2010. Impulsnaia promyvka skvazhin [Pulse flushing of drilling holes]. Donetsk: “Knowledge” Publishing House.

Кожевников А. А. Импульсная промывка скважин / Кожевников А. А., Филлимоненко Н. В., Жикаляк Н. В. – Донецк: Изд-во „Ноулидж“ (Донецкое отд.), 2010. – 275 с.

2. Dreus, A., Kozhevnikov, A., Sudakov, A. and Lysenko, K., 2016. Investigation of heating of the drilling bits and definition of the energy efficient drilling modes. Eastern-European Journal of Enterprise Technologies, No. 3/7 (81), pp. 41–46.

3. Abukhshim, N. A., Mativenga, P. T. and Sheikh, M. A., 2006. Heat generation and temperature prediction in metal cutting: A review and implications for high speed machining. International Journal of Machine Tools & Manufacture, No. 46, pp. 782–800.

4. Kozhevnikov, A. A., Goshovskyi, S. V., Dreus, A. Yu. and Martynenko, I. I., 2008. Teplovoi factor pri burenii skvazhin [Heat factor in the course of well drilling]. Kiev: Ukrainian State Mining Exploration Publishing House.

Тепловой фактор при бурении скважин / Кожевников А. А., Гошовский С. В., Дреус А. Ю., Мартыненко И. И. – К.: Изд-во УкрГГРИ, 2008. – 166 с.

5. Zhao Jian, Xu Yiji, Ren Jianhua and Hou Deju, 2014. Numerical Simulation of the Bottom Hole Flow Field of Particle Impact Drilling. Advances in Petroleum Exploration and Development, Vol. 8 (02), рр. 18–23.

6. Yu-Ying Zhang, Yong-Wang Liu, Yi-Ji Xu and Jian-Hua Ren, 2011. Drilling characteristics of combinations of different high pressure jet nozzles. Journal of Hydrodynamics. Ser. B. , Vol. 23 (3), рр. 384–390.

7. Chang-Heon Song, Ki-Beom Kwon, Jin-Young Park, Joo-Young Oh, Shinok Lee, Dae-Young Shin and Jung-Woo Cho, 2014. Optimum Design of the Internal Flushing Channel of a Drill Bit using RSM and CFD Simulation. International journal of precision engineering and manufacturing, Vol. 15(6), рр. 1041– 1050.

8. Khrutskyi, A. A., 2009. Mathematical modeling of flange bit flow-over with pressed air in the course of drilling in the environment COSMOSFloWorks. Naukovyi Visnyk Natsіonalnoho Hіrnychoho Unіversitetu, No. 11, рр. 38–42.

Хруцкий А. А. Математическое моделирование процесса обтекания штыревой коронки сжатым воздухом при бурении в среде COSMOSFloWorks / А. А. Хруцкий // Науковий вісник Національного гірничого університету. – 2009. – № 11. – С. 38–42.

9. Chen Yan, Liu Zhiyi and Duan Longchen, 2012. Simulation on hydraulic performance of two kinds of coring diamond bits with different crown. Advanced Materials Research, Vol. 497, рр. 350–355.

10. Karakozov, A. A., Popova, M. S., Parfenyuk, S. N., Bogdanov, R. K. and Zakora, A. P., 2013. Creation of single-layered diamond drilling bits equipped with synthetic mono-crystals. Scinetific articles of Donetsk National Technical University. Ser : Mining exploration, No. 2, рр. 245–252.

Создание однослойных алмазных коронок, оснащённых синтетическими монокристаллами / А. А. Каракозов, М. С. Попова, С. Н. Парфенюк [и др.] // Наукові праці Донецького національного технічного університету. Серія: Гірничо-геологічна – 2013. – № 2. – С. 245–252.

11. Dreus, A. Yu., Kozhevnikov, A. A., Sudakov, A. K., Vakhalin, Yu. M., 2016. Study on thermal strength reduction of rock formation in the diamond core drilling process using pulse flushing mode. Naukovyi Visnyk Natsіonalnoho Hіrnychoho Unіversitetu, No. 3, рр. 5–10.

Исследование термического разупрочнения горной породі при бурении с импульсной промывкой / А. Ю. Дреус, А. А. Кожевников, А. К. Судаков, Ю. Н. Вахалин // Науковий вісник Національного гірничого університету. – 2016. – № 3. – С. 5–10.

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