A rocket motor (20) includes a nozzle (22) and a solid propellant section (24) in communication with the nozzle. The solid propellant section includes a first energetic grain layer (38, 32) that has a top surface and a bottom surface, and a second energetic grain layer (40, 44) that has a top surface and a bottom surface. The second layer is located on top of the first layer. The bottom surface of the second energetic grain layer partially abuts the top surface of the first energetic grain layer, and the bottom surface of the second energetic grain layer and the top surface of the first energetic grain layer define a region (46, 48) therebetween. A powder energetic (49) is disposed in the region.

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 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 hybrid rocket solid fuel grain having a cylindrical shape and defining a center port is additive manufactured from a compound of thermoplastic fuel and passivated nanocomposite aluminum additive. The fuel grain comprises a stack of fused layers, each layer formed as a plurality of fused abutting concentric circular beaded structures arrayed to define a center port. During operation, an oxidizer is introduced along the center port, with combustion occurring along the exposed port wall. Each circular beaded structure defines geometry that increases the surface area available for combustion. As each layer ablates the next 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. To safely achieve this construction, a fused deposition additive manufacturing apparatus, modified to shield the nanocomposite material from the atmosphere, is used.

A hybrid rocket solid fuel grain having a cylindrical shape and defining a center port is additive manufactured from a compound of thermoplastic fuel and passivated nanocomposite aluminum additive. The fuel grain comprises a stack of fused layers, each layer formed as a plurality of fused abutting concentric circular beaded structures arrayed to define a center port. During operation, an oxidizer is introduced along the center port, with combustion occurring along the exposed port wall. Each circular beaded structure defines geometry that increases the surface area available for combustion. As each layer ablates the next 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. To safely achieve this construction, a fused deposition additive manufacturing apparatus, modified to shield the nanocomposite material from the atmosphere, is used.

A gas generator includes an outer propellant, an inner propellant arranged inside the outer propellant, and a barrier membrane which isolates the outer propellant from the inner propellant. A forward end surface of the inner propellant faces a combustion space. A side surface of the inner propellant is isolated from the combustion space.

A method of making a fuel grain for use in a rocket motor, the method comprising blending a first energetic nanoscale metallic compound and a second compound suitable to form a feedstock material for use in an additive manufacturing apparatus, the additive manufacturing apparatus operatively connected to a computing system, that provides additive manufacturing printing instructions to the additive manufacturing apparatus, permitting construction of an autonomously designed and optimized rocket fuel grain section; wherein the stochastic deposition simulation-assisted fuel grain geometries further comprise a plurality of agglutinated layers of solidified fuel grain compound, each layer of the plurality of layers comprising a plurality of blended and radially displaced beads of different radii, said radial displacement optionally optimized via competitive simulation programs, and wherein the system continuously mixes constituent materials in an inline/static mixer, with viscosity controlled via particle size variations, and material is deposited in a controlled atmosphere or vacuum.

A method of making a fuel grain for use in a rocket motor, the method comprising blending a first energetic nanoscale metallic compound and a second compound suitable to form a feedstock material for use in an additive manufacturing apparatus, the additive manufacturing apparatus operatively connected to a computing system, that provides additive manufacturing printing instructions to the additive manufacturing apparatus, permitting construction of an autonomously designed and optimized rocket fuel grain section; wherein the stochastic deposition simulation-assisted fuel grain geometries further comprise a plurality of agglutinated layers of solidified fuel grain compound, each layer of the plurality of layers comprising a plurality of blended and radially displaced beads of different radii, said radial displacement optionally optimized via competitive simulation programs, and wherein the system continuously mixes constituent materials in an inline/static mixer, with viscosity controlled via particle size variations, and material is deposited in a controlled atmosphere or vacuum.

A fuel grain for a rocket, the fuel grain having a plurality of layers of fuel grain material, each layer comprising a plurality of concentric circular structures of different diameter fused together to form a central opening therein, wherein the fuel grain material comprises an ignitable substance. The plurality of layers are stacked and joined securely to form a cylindrical fuel grain with the central opening of each one of the plurality of layers aligned to form a combustion unit extending axially through the fuel grain and bounded by a combustion surface, and wherein the fuel grain is configured to permit mixing of heterogenous materials to enhance thrust performance.

A fuel grain for a rocket, the fuel grain having a plurality of layers of fuel grain material, each layer comprising a plurality of concentric circular structures of different diameter fused together to form a central opening therein, wherein the fuel grain material comprises an ignitable substance. The plurality of layers are stacked and joined securely to form a cylindrical fuel grain with the central opening of each one of the plurality of layers aligned to form a combustion unit extending axially through the fuel grain and bounded by a combustion surface, and wherein the fuel grain is configured to permit mixing of heterogenous materials to enhance thrust performance.