Elastic Relaxation of Fluid-Driven Cracks and the Resulting Backflow.

TitleElastic Relaxation of Fluid-Driven Cracks and the Resulting Backflow.
Publication TypeJournal Article
Year of Publication2016
AuthorsLai, C-Y, Zheng, Z, Dressaire, E, Ramon, GZ, Huppert, HE, Stone, HA
JournalPhys Rev Lett
Date Published2016 Dec 23

<p>Cracks filled with fluid propagation when the pressurized fluid is injected into the crack. Subsequently, when the fluid inlet is exposed to a lower pressure, the fluid flows backwards (backflow) and the crack closes due to the elastic relaxation of the solid. Here we study the dynamics of the crack closure during the backflow. We find that the crack radius remains constant and the fluid volume in the crack decreases with time in a power-law manner at late times. The balance between the viscous stresses in the fluid and elastic stresses in the fluid and the elastic stresses in the solid yields a scaling law that agrees with the experimental results for different fluid viscosities, Young's moduli of the solid, and initial radii of the cracks. Furthermore, we visualize the time-dependent crack shapes, and the convergence to a universal dimensionless shape demonstrates the self-similarity of the crack shapes during the backflow process.</p>

Alternate JournalPhys Rev Lett
PubMed ID28059547