A cylindrically-shaped hybrid rocket engine solid fuel grain defines an axial combustion port. A fuel grain material comprises a compounded blend of thermoplastic fuel and aluminum. The fuel grain comprises fused stack layers, each layer comprising a plurality of fused abutting concentric beaded structures arrayed to define the combustion port; the port exhibits a rifling pattern or rifling inducing geometry along the port wall. When an oxidizer is introduced into the combustion port combustion occurs along the exposed port wall. Each beaded structure defines a geometry that increases the combustion surface area while inducing a vortex flow of oxidizer and fuel gas. As each layer ablates, an abutting layer exhibiting a similar geometry, is revealed, undergoes a gas phase change, and ablates. This process repeats and persists until oxidizer flow is terminated or the fuel grain material is exhausted. The fuel grain may be manufactured by an additive manufacturing process.

An inflator (10) is actuatable to provide inflation fluid for inflating an inflatable vehicle occupant protection device. The inflator (10) includes a volume of stored gas and a propellant (52) that is ignitable to undergo a reaction that produces reaction products. The reaction products include heat and gas that mix with the stored gas to produce a mixture of inflation fluid. The inflator (10) is configured to discharge the inflation fluid to inflate the protection device. The propellant (52) comprises an open cell foam fuel propellant (140). The reaction includes a combustion reaction in which the foam fuel propellant (140) reacts with a gas oxidizer comprising oxygen to produce heat and gas reaction products that mix with the stored gas.

An inflator (10) is actuatable to provide inflation fluid for inflating an inflatable vehicle occupant protection device. The inflator (10) includes a volume of stored gas and a propellant (52) that is ignitable to undergo a reaction that produces reaction products. The reaction products include heat and gas that mix with the stored gas to produce a mixture of inflation fluid. The inflator (10) is configured to discharge the inflation fluid to inflate the protection device. The propellant (52) comprises an open cell foam fuel propellant (140). The reaction includes a combustion reaction in which the foam fuel propellant (140) reacts with a gas oxidizer comprising oxygen to produce heat and gas reaction products that mix with the stored gas.

A method of treating a subterranean formation by contacting the formation with the following (a) ammonium bicarbonate; (b) and oxidizing agent selected from a perchlorate or a nitrite or combinations thereof; and (c) an acid (AA).

A cylindrically-shaped hybrid rocket engine solid fuel grain defines an axial combustion port. A fuel grain material comprises a compounded blend of thermoplastic fuel and aluminum. The fuel grain comprises fused stack layers, each layer comprising a plurality of fused abutting concentric beaded structures arrayed to define the combustion port; the port exhibits a rifling pattern or rifling inducing geometry along the port wall. When an oxidizer is introduced into the combustion port combustion occurs along the exposed port wall. Each beaded structure defines a geometry that increases the combustion surface area while inducing a vortex flow of oxidizer and fuel gas. As each layer ablates, an abutting layer exhibiting a similar geometry, is revealed, undergoes a gas phase change, and ablates. This process repeats and persists until oxidizer flow is terminated or the fuel grain material is exhausted. The fuel grain may be manufactured by an additive manufacturing process.

A method of treating a subterranean formation by contacting the formation with the following (a) ammonium bicarbonate; (b) an oxidizing agent selected from a perchlorate or a nitrite or combinations thereof; and (c) an acid (AA).

An inflator (10) is actuatable to provide inflation fluid for inflating an inflatable vehicle occupant protection device. The inflator (10) includes a volume of stored gas and a propellant (52) that is ignitable to undergo a reaction that produces reaction products. The reaction products include heat and gas that mix with the stored gas to produce a mixture of inflation fluid. The inflator (10) is configured to discharge the inflation fluid to inflate the protection device. The propellant (52) comprises an open cell foam fuel propellant (140). The reaction includes a combustion reaction in which the foam fuel propellant (140) reacts with a gas oxidizer comprising oxygen to produce heat and gas reaction products that mix with the stored gas.

A high density, generally recognized as safe hybrid rocket motor is described which has a density-specific impulse similar to a solid rocket motor, with good performance approaching or equal to a liquid rocket motor. These high density hybrid motors resolve the packaging efficiency/effectiveness problems limiting the application of safe, low cost hybrid motor technology.

A multi-compartment microcapsule produces heat when subjected to a stimulus (e.g., a compressive force, a magnetic field, or combinations thereof). In some embodiments, the multi-compartment microcapsules have first and second compartments separated by an isolating structure adapted to rupture in response to the stimulus, wherein the first and second compartments contain reactants that come in contact and react to produce heat when the isolating structure ruptures. In some embodiments, the multi-compartment microcapsules are shell-in-shell microcapsules each having an inner shell contained within an outer shell, wherein the inner shell defines the isolating structure and the outer shell does not allow the heat-generating chemistry to escape the microcapsule upon rupture of the inner shell.

A multi-compartment microcapsule produces heat when subjected to a stimulus (e.g., a compressive force, a magnetic field, or combinations thereof). In some embodiments, the multi-compartment microcapsules have first and second compartments separated by an isolating structure adapted to rupture in response to the stimulus, wherein the first and second compartments contain reactants that come in contact and react to produce heat when the isolating structure ruptures. In some embodiments, the multi-compartment microcapsules are shell-in-shell microcapsules each having an inner shell contained within an outer shell, wherein the inner shell defines the isolating structure and the outer shell does not allow the heat-generating chemistry to escape the microcapsule upon rupture of the inner shell.