| 摘要 |
A propellant is ignited within a well to rapidly produce combustion gases to generate pressure exceeding the fracture extension pressure of the surrounding formation. Combustion gases are generated at a rate greater than can be absorbed into any single fracture, thereby causing propagation of multiple fractures into the surrounding formation. In one embodiment, each segment of the propellant is in the form of a solid cylindrical body of fuel/oxidizer surrounded by an expandable casing made of a material similar to a fire hose. A linear shaped charge extends between the casing and the propellant. Upon ignition of the shaped charge, combustion gases quickly stretch the casing thereby allowing the hot gases to surround and ignite the entire propellant surface area. The propellant then burns in a radially inward direction in a predictable manner. A computer program can be used to model the burn rate of the propellant to predict the resulting generation of combustion gases and fracture propagation, and thereby determine a suitable quantity and configuration of the propellant for creating multiple fractures in the surrounding formation.
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