Permeability Enhancement Technology for Soft and Low-Permeability Coal Seams Combined with Hydraulic Perforation and Hydraulic Fracturing

The Calculation Model of Initiation Pressure During Hydraulic Fracturing Process of Perforated Coal Seams

There are lots of cleats, fractures and many other structure weak planes in coal seams, which make the bullet holes and cleats intersecting. During the hydraulic fracturing process in coal seams, fractures will initiate at coal rock body of borehole wall, and cleats or fractures are different from conventional reservoirs. Thus a new model for initiation pressure calculation during coal seams fr...

Tooth Pulp Tissue Pressure and Hydraulic Permeability.

• If the pulp chamber of a tooth is penetrated, either by dental caries, or by a dental drill, inflammation and eventual death of the pulp tissue usually follows. While a long interval may elapse before degeneration is complete, necrosis is an almost inevitable consequence of pulpal penetration. A current explanation in the dental literature for this phenomenon is as follows. The application of...

Hydraulic and Pneumatic Fracturing

Anisotropic hydraulic permeability under finite deformation.

The structural organization of biological tissues and cells often produces anisotropic transport properties. These tissues may also undergo large deformations under normal function, potentially inducing further anisotropy. A general framework for formulating constitutive relations for anisotropic transport properties under finite deformation is lacking in the literature. This study presents an ...

Complex Fluids and Hydraulic Fracturing.

Nearly 70 years old, hydraulic fracturing is a core technique for stimulating hydrocarbon production in a majority of oil and gas reservoirs. Complex fluids are implemented in nearly every step of the fracturing process, most significantly to generate and sustain fractures and transport and distribute proppant particles during and following fluid injection. An extremely wide range of complex fl...