Pressure interfacial fracture

However, it may be practically impossible to increase the viscosity or velocity by such a magnitude because doing so would require or result in a very high pressure difference between the injector and producer. Such high pressure difference would fracture the formation. Another way to increase capillary number is to reduce interfacial tension, which can be achieved through injection of surfactants. Recall that ultralow interfacial tension is one of the main mechanisms in surfactant-related processes. 

The stress-mediated redistribution of mineral mass by pressure solution may be represented by the three serial processes of mineral dissolution beneath the contacting asperity, transport along an interfacial water-film to the fracture void, and then redistribution by precipitation within the fracture void, or efflux from the sample. The asperities interpenetrate as mass is removed from contacting asperities, in a similar manner to the mechanisms that drive grain interpenetration and cementation in sandstones [Yasuhara et al., 2003], as illustrated in Figure 10. 

For a wide range of materials the emission of electrons (EE), positive ions (PIE), neutral species (NE), and photons (phE) has been observed accompanying fracture. We refer collectively to these emissions as fracto-emission. In this paper we review our work on fracto-emission where the fracture event involves interfacial or adhesive failure. The interfaces to be discussed include the following brittle materials/epoxy, glass/elastomers, and brittle materials/pressure sensitive adhesives. 

Finally, we may look at the theory that we have developed from the viewpoint of catastrophe theory. Filament rupture is intrinsically a catastrophe, and so is interfacial separation. The peeling of a pressure-sensitive tape and the propagation of a fracture front are macroscopically continuous processes, but the change in behavior of individual filaments or fibers in the separation front is discontinuous either they detach from the solid or they rupture. Thus, the microscopic course of events is subject to a bifurcation, i.e., a choice between two catastrophes. 

The cross-sections of impression for different combination of specimen and indenter size are shown in from Figs. 13 to Fig. 16. For the observation of plastic zone immediately below the impression" . While there was little distinction in the fracture of spray film and the formation of plastic zone in different specimens, they presented clear differences depending on the indenter size. In case of indenter 1 mminterfacial debonding" . As the indenter size increased, the fracture tended to turn closer to the interfacial debonding. With smaller indenter, the indentation pressure is greater, to produce plastic deformation in the substrate. With 1 mmc[) indenter, plastic deformation occurred in proportion to the size of damage area, while with 4mmc[) indenter, the plastic... 

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