A method of reducing low-energy flow in a flight vehicle engine includes an isolator of the engine having a swept-back wedge to improve flow mixing. The wedge includes forward shock-anchoring locations, such as edges or rapidly-curved portions, that anchor oblique shocks in situations where the isolator has sufficient back pressure. The swept-back wedge may also create swept oblique shocks along its length. Boundary layer flow streamlines are diverted running parallel to or parallel but moving outward conically to the swept-wedge leading edge moving outboard and upward. The non-viscous flow outside the boundary layer is processed through the swept-back ramp shock and diverted outboard and upward as well. The outboard aft portion of the wedge at the sidewall intersection may also induce shocks and divert flow near the walls closer toward the walls and upward, and/or improve flow mixing.

A method of reducing low-energy flow in a flight vehicle engine includes an isolator of the engine having a swept-back wedge to improve flow mixing. The wedge includes forward shock-anchoring locations, such as edges or rapidly-curved portions, that anchor oblique shocks in situations where the isolator has sufficient back pressure. The swept-back wedge may also create swept oblique shocks along its length. Boundary layer flow streamlines are diverted running parallel to or parallel but moving outward conically to the swept-wedge leading edge moving outboard and upward. The non-viscous flow outside the boundary layer is processed through the swept-back ramp shock and diverted outboard and upward as well. The outboard aft portion of the wedge at the sidewall intersection may also induce shocks and divert flow near the walls closer toward the walls and upward, and/or improve flow mixing.

A satellite has thrusters that are integral parts of its frame. The frame defines cavities therein where thrusters are located. The thrusters may include an electrically-operated propellant and electrodes to activate combustion in the electrically-operated propellant. The frame may be additively manufactured, and the propellant and/or the electrodes may also be additively manufactured, with the frame and the propellant and/or the electrodes also being manufactured in a single process. In addition the thrusters may have nozzle portions through which combustion gases exit the thrusters. The thrusters may be located at corners and/or along edges of the frame, and may be used to accomplish any of a variety of maneuvers for the satellite. The satellite may be a small satellite, such as a CubeSat satellite, for instance having a volume of about 1 liter, and a mass of no more than about 1.33 kg.

Techniques, devices and systems are disclosed for implementing acoustically triggered propulsion of nano- and micro-scale structures. In one aspect, an ultrasound responsive propulsion device includes a tube that includes one or more layers including an inner layer having an electrostatic surface, and an ultrasound-responsive substance coupled to the inner layer and configured to form gaseous bubbles in a fluid in response to an ultrasound pulse, in which the bubbles exit the tube to propel the tube to move in the fluid.

The jet engine comprising a ramjet air path extending from an intake, into a combustion chamber, and out an exhaust nozzle, a fuel inlet leading into the combustion chamber, an oxidizer inlet leading into the combustion chamber and a partition being operable to selectively close the ramjet air path upstream of the combustion chamber to allow operation of the jet engine in rocket mode and open the ramjet air path to allow operation of the jet engine in ramjet mode.

The invention relates to a ramjet including a detonation chamber and an aircraft comprising such a ramjet. According to the invention, the ramjet (S1) comprises an annular detonation chamber (2) having a continuous detonation wave and fuel injection means (6) for continuously injecting fuel (F2) directly into the chamber (2) just downstream of an air injection base (3). The fuel (F2) and the air (F1) are injected separately into the detonation chamber (2) in a permanent manner throughout the operation of the ramjet (S1).

An inlet arrangement is disclosed herein for use with a supersonic jet engine configured to consume air at a predetermined mass flow rate when the supersonic jet engine is operating at a predetermined power setting and moving at a predetermined Mach speed. The air inlet arrangement includes, but is not limited to, a cowl having a cowl lip and a center body coaxially aligned with the cowl. A protruding portion of the center body extends upstream of the cowl lip for a length greater than a conventional spike length. The protruding portion is configured to divert air flowing over the protruding portion out of a pathway of an inlet to the supersonic jet engine such that a remaining airflow approaching and entering the inlet matches the predetermined mass flow rate.

An inlet arrangement is disclosed herein for use with a supersonic jet engine configured to consume air at a predetermined mass flow rate when the supersonic jet engine is operating at a predetermined power setting and moving at a predetermined Mach speed. The air inlet arrangement includes, but is not limited to, a cowl having a cowl lip and a center body coaxially aligned with the cowl. A protruding portion of the center body extends upstream of the cowl lip for a length greater than a conventional spike length. The protruding portion is configured to divert air flowing over the protruding portion out of a pathway of an inlet to the supersonic jet engine such that a remaining airflow approaching and entering the inlet matches the predetermined mass flow rate.

A jet engine has an inlet which takes in air, a combustor which combusts fuel by using the air, and a fuel control section which controls supply of the fuel. The combustor has a fuel supplying section which supplies the fuel, injectors which inject the fuel. Each injector contains openings which inject the fuel. The fuel supplying section supplies the fuel to the injector in a flow rate according to a command of an autopilot. The fuel control section controls the injectors such that the number of the openings which inject the fuel or flow-path cross-section areas of the pipes which send the fuel in case of the low-speed is more than the number of the openings which inject the fuel or the flow-path cross-section areas of the pipes which send the fuel in case of the high-speed.

A jet engine has an inlet which takes in air, a combustor which combusts fuel by using the air, and a fuel control section which controls supply of the fuel. The combustor has a fuel supplying section which supplies the fuel, injectors which inject the fuel. Each injector contains openings which inject the fuel. The fuel supplying section supplies the fuel to the injector in a flow rate according to a command of an autopilot. The fuel control section controls the injectors such that the number of the openings which inject the fuel or flow-path cross-section areas of the pipes which send the fuel in case of the low-speed is more than the number of the openings which inject the fuel or the flow-path cross-section areas of the pipes which send the fuel in case of the high-speed.