A photonic reflector device includes a first layer, a second layer, and a third layer. The first layer, which functions as a retro-reflector, is formed of a first material contacting a second material and having a non-planar interface therebetween. The second layer, which functions as a photonic crystal, includes third and fourth materials that have different refractive indices from one another and are configured such that the second layer has a periodic optical potential along at least one dimension. The third layer, which functions as a Lambertian scatterer, includes a plurality of inclusions in a first matrix material. In combination, the layers may be optimized to synergistically reflect targeted wavelengths and/or polarizations of light.

A photonic reflector device includes a first layer, a second layer, and a third layer. The first layer, which functions as a retro-reflector, is formed of a first material contacting a second material and having a non-planar interface therebetween. The second layer, which functions as a photonic crystal, includes third and fourth materials that have different refractive indices from one another and are configured such that the second layer has a periodic optical potential along at least one dimension. The third layer, which functions as a Lambertian scatterer, includes a plurality of inclusions in a first matrix material. In combination, the layers may be optimized to synergistically reflect targeted wavelengths and/or polarizations of light.

A combustion chamber including a diverging portion. The combustion chamber extends along a longitudinal axis and includes a fluid injection system from which there extends in a downstream direction a wall presenting a throat and a diverging portion situated downstream from the throat. The chamber further includes a tubular element surrounding the wall at least in part and configured to take up most of forces generated during operation of the chamber on the downstream end of the wall to transfer the forces to a structure situated upstream from the chamber.

A combustion chamber including a diverging portion. The combustion chamber extends along a longitudinal axis and includes a fluid injection system from which there extends in a downstream direction a wall presenting a throat and a diverging portion situated downstream from the throat. The chamber further includes a tubular element surrounding the wall at least in part and configured to take up most of forces generated during operation of the chamber on the downstream end of the wall to transfer the forces to a structure situated upstream from the chamber.

The invention relates to a thrust chamber device, comprising a thrust chamber with a thrust space that has a first portion, a second portion adjoining the first portion, and a third portion adjoining the second portion, wherein the thrust space is delimited in all three portions by an outer nozzle wall with an outer thrust space surface, which outer thrust space surface tapers in the first and second portion toward the third portion and in the third portion expands away from the second portion, wherein a narrowest point is formed at the transition from the second portion to the third portion, wherein the first portion is delimited by an inner nozzle wall with an inner thrust space surface, and wherein the thrust chamber device comprises a regenerative cooling unit for cooling the inner nozzle wall and the outer nozzle wall with a coolant.

A high-temperature component according to an embodiment is a high-temperature component which requires cooling by a cooling medium, and includes: a plurality of cooling passages through which the cooling medium is able to flow; a header portion to which downstream ends of the plurality of first cooling passages are connected; and at least one outlet passage for discharging the cooling medium flowing into the header portion to outside of the header portion. A roughness of an inner wall surface of the at least one outlet passage is not greater than a roughness of an inner wall surface of the plurality of first cooling passages in a region where a flow-passage cross-sectional area of the outlet passage is the smallest.

A multi-pulse gas generator includes a pressure vessel, first and second propellants, a barrier membrane that separates the first propellant and the second propellant, an igniter device that produces combustion gas of igniter charge, and an igniter charge combustion gas exhaust device having exhaust holes configured to exhaust the combustion gas of the igniter charge against the second propellant. The barrier membrane includes: a concavely-deformable portion; and a convexly-deformable portion. A flow rate of the combustion gas of the igniter charge exhausted against a portion of the second propellant located outside of the concavely-deformable portion is larger than that of the combustion gas of the igniter charge exhausted against a portion of the second propellant located outside of the convexly-deformable portion.

A multi-pulse gas generator includes a pressure vessel, first and second propellants, a barrier membrane that separates the first propellant and the second propellant, an igniter device that produces combustion gas of igniter charge, and an igniter charge combustion gas exhaust device having exhaust holes configured to exhaust the combustion gas of the igniter charge against the second propellant. The barrier membrane includes: a concavely-deformable portion; and a convexly-deformable portion. A flow rate of the combustion gas of the igniter charge exhausted against a portion of the second propellant located outside of the concavely-deformable portion is larger than that of the combustion gas of the igniter charge exhausted against a portion of the second propellant located outside of the convexly-deformable portion.

An emergency landing apparatus for an aircraft and a method of operating the emergency landing apparatus is provided. The emergency landing apparatus comprises: one or more rocket motors arranged to eject efflux in order to provide upwards thrust to control descent of the aircraft during emergency landing of the aircraft; and control circuitry configured to: cause the one or more rocket motors to eject efflux and provide upwards thrust to control descent of the aircraft during emergency landing of the aircraft; and cause redirection of the efflux ejected by the one or more rocket motors, during the emergency landing of the aircraft, in order to reduce the upwards thrust provided by the one or more rocket motors.

A high-temperature component according to an embodiment is a high-temperature component which requires cooling by a cooling medium, and includes: a plurality of cooling passages through which the cooling medium is able to flow; a header portion to which downstream ends of the plurality of first cooling passages are connected; and at least one outlet passage for discharging the cooling medium flowing into the header portion to outside of the header portion. A roughness of an inner wall surface of the at least one outlet passage is not greater than a roughness of an inner wall surface of the plurality of first cooling passages in a region where a flow-passage cross-sectional area of the outlet passage is the smallest.