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Experimental exploration of fluid-driven cracks in brittle hydrogels

Published online by Cambridge University Press:  12 April 2018

Niall J. O’Keeffe*
Affiliation:
Department of Applied Mathematics and Theoretical Physics, University of Cambridge, Wilberforce Road, Cambridge CB3 0WA, UK
Herbert E. Huppert
Affiliation:
Department of Applied Mathematics and Theoretical Physics, University of Cambridge, Wilberforce Road, Cambridge CB3 0WA, UK
P. F. Linden
Affiliation:
Department of Applied Mathematics and Theoretical Physics, University of Cambridge, Wilberforce Road, Cambridge CB3 0WA, UK
*
Email address for correspondence: [email protected]

Abstract

Hydraulic fracturing is a procedure by which a fracture is initiated and propagates due to pressure (hydraulic loading) applied by a fluid introduced inside the fracture. In this study, we focus on a crack driven by an incompressible Newtonian fluid, injected at a constant rate into an elastic matrix. The injected fluid creates a radial fracture that propagates along a plane. We investigate this type of fracture both theoretically and experimentally. Our experimental apparatus uses a brittle and transparent polyacrylamide hydrogel matrix. Using this medium, we examine the rate of radial crack growth, fracture aperture, shape of the crack tip and internal fluid flow field. Our range of experimental parameters allows us to exhibit two distinct fracturing regimes, and the transition between these, in which the rate of radial crack propagation is dominated by either viscous flow within the fracture or the material toughness. Measurements of the profiles near the crack tip provide additional evidence of the viscosity-dominated and toughness-dominated regimes, and allow us to observe the transition from the viscous to the toughness regime as the crack propagates. Particle image velocimetry measurements show that the flow in the crack is radial, as expected in the viscous regime and in the early stages of the toughness regime. However, at later times in the toughness regime, circulation cells are observed in the flow within the crack that destroy the radial symmetry of the flow field.

Type
JFM Papers
Copyright
© 2018 Cambridge University Press 

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References

Alpern, J. S., Marone, C. J., Elsworth, D., Belmonte, A. & Connelly, P. 2012 Exploring the physicochemical processes that govern hydraulic fracture through laboratory experiments. In 46th US Rock Mechanics/Geomechanics Symposium, ARMA.Google Scholar
Batchelor, G. K. 1967 An Introduction to Fluid Dynamics. Cambridge University Press.Google Scholar
Bunger, A. P. 2006 A photometry method for measuring the opening of fluid-filled fractures. Meas. Sci. Technol. 17 (12), 32373244.10.1088/0957-0233/17/12/006Google Scholar
Bunger, A. P. & Detournay, E. 2007 Early-time solution for a radial hydraulic fracture. ASCE J. Engng Mech. 133 (5), 534540.10.1061/(ASCE)0733-9399(2007)133:5(534)Google Scholar
Bunger, A. P. & Detournay, E. 2008 Experimental validation of the tip asymptotics for a fluid-driven crack. J. Mech. Phys. Solids 56 (11), 31013115.10.1016/j.jmps.2008.08.006Google Scholar
Dalziel, S. B.2006 Digiflow user guide. DL Research Partners, version 1.Google Scholar
Detournay, E. & Garagash, D. I. 2003 The near-tip region of a fluid-driven fracture propagating in a permeable elastic solid. J. Fluid Mech. 494, 132.10.1017/S0022112003005275Google Scholar
Economides, M. J. & Nolte, K. G. 2000 Reservoir Stimulation, vol. 18. Wiley.Google Scholar
Fairhurst, C. 1964 Measurement of in-situ rock stresses. With particular reference to hydraulic fracturing. Rock Mechanics (United States) 2.Google Scholar
Garagash, D., Detournay, E. & Adachi, J. 2011 Multiscale tip asymptotics in hydraulic fracture. J. Fluid Mech. 669, 260297.10.1017/S002211201000501XGoogle Scholar
Garagash, D. I. & Detournay, E. 2000 The tip region of a fluid-driven fracture in an elastic medium. Trans. ASME J. Appl. Mech. 67 (1), 183192.10.1115/1.321162Google Scholar
Garagash, D. I. & Detournay, E. 2005 Plane-strain propagation of a fluid-driven fracture: small toughness solution. Trans. ASME J. Appl. Mech. 72 (6), 916928.10.1115/1.2047596Google Scholar
Hubbert, M. K. & Willis, D. G. 1957 Mechanics of hydraulic fracturing. J. Petrol. Tech. 9 (6), 153166.Google Scholar
Huppert, H. E. & Neufeld, J. A. 2014 The fluid mechanics of carbon dioxide sequestration. Annu. Rev. Fluid Mech. 46, 255272.10.1146/annurev-fluid-011212-140627Google Scholar
Kanninen, M. F. & Popelar, C. L. 1985 Advanced Fracture Mechanics. Oxford University Press.Google Scholar
Lai, C. Y., Zheng, Z., Dressaire, E. & Stone, H. A. 2016 Fluid-driven cracks in an elastic matrix in the toughness-dominated limit. Phil. Trans. R. Soc. Lond. A 374 (2078), 20150425.Google Scholar
Lai, C. Y., Zheng, Z., Dressaire, E., Wexler, J. S. & Stone, H. A. 2015 Experimental study on penny-shaped fluid-driven cracks in an elastic matrix. Proc. R. Soc. Lond. A 471 (2182), 20150255.Google Scholar
Lister, J. R. & Kerr, R. C. 1991 Fluid-mechanical models of crack propagation and their application to magma transport in dykes. J. Geophys. Res. 96 (B6), 1004910077.10.1029/91JB00600Google Scholar
Livne, A., Cohen, G. & Fineberg, J. 2005 Universality and hysteretic dynamics in rapid fracture. Phys. Rev. Lett. 94 (22), 224301.10.1103/PhysRevLett.94.224301Google Scholar
Mair, R. & Hight, D. 1994 Compensation grouting. World Tunnelling and Subsurface Excavation 7 (8), 361367.Google Scholar
Murphy, H. D., Tester, J. W., Grigsby, C. O. & Potter, R. M. 1981 Energy extraction from fractured geothermal reservoirs in low-permeability crystalline rock. J. Geophys. Res. 86 (B8), 71457158.10.1029/JB086iB08p07145Google Scholar
O’Keeffe, N. J. & Linden, P. F. 2017 Hydrogel as a medium for fluid-driven fracture study. Exp. Mech. 57 (9), 14831493.10.1007/s11340-017-0314-yGoogle Scholar
Rice, J. R. 1968 Mathematical analysis in the mechanics of fracture. Fracture: an Advanced Treatise. vol. 2, pp. 191311. Academic Press.Google Scholar
Rudnicki, J. W. 2000 Geomechanics. Intl J. Solids Struct. 37 (1), 349358.10.1016/S0020-7683(99)00098-0Google Scholar
Savitski, A. A. & Detournay, E. 2002 Propagation of a penny-shaped fluid-driven fracture in an impermeable rock: asymptotic solutions. Intl J. Solids Struct. 39 (26), 63116337.10.1016/S0020-7683(02)00492-4Google Scholar
Sneddon, I. N. 1946 The distribution of stress in the neighbourhood of a crack in an elastic solid. Proc. R. Soc. Lond. A 187, 229260.Google Scholar
Sneddon, I. N. 1951 Fourier Transforms. McGraw-Hill.Google Scholar
Sneddon, I. N. & Lowengrub, M. 1969 Crack Problems in the Classical Theory of Elasticity. Wiley.Google Scholar
Spence, D. A. & Sharp, P. 1985 Self-similar solutions for elastohydrodynamic cavity flow. Proc. R. Soc. Lond. A 400 (1819), 289313.Google Scholar
Takada, A. 1990 Experimental study on propagation of liquid-filled crack in gelatin: shape and velocity in hydrostatic stress condition. J. Geophys. Res. 95 (B6), 84718481.10.1029/JB095iB06p08471Google Scholar
Tanaka, Y., Fukao, K. & Miyamoto, Y. 2000 Fracture energy of gels. Eur. Phys. J. E 3 (4), 395401.Google Scholar
Tanaka, Y., Fukao, K., Miyamoto, Y., Nakazawa, H. & Sekimoto, K. 1996 Regular patterns on fracture surfaces of polymer gels. J. Phys. Soc. Japan 65 (8), 23492352.10.1143/JPSJ.65.2349Google Scholar
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