Abstract: Embodiments of the present invention provide a Streamline Traced External Compression Inlet (STECI) that represents a new solution to external compression inlet integration issues. STECI utilizes a Computational Fluid Dynamics (CFD) solution produced by a shock-generating shape which is defined by a conceptual design trade study. The shock generating shape may be created by single or multiple surfaces depending on number of upstream oblique shocks required to produce desired flow characteristics at the throat of the inlet. An aperture is then defined according to shaping requirements. This desired aperture is projected onto the forward-most, and aft-most oblique shocks of the flow field. The projected cowl portion of the aperture is then offset downstream from the aft-most oblique shock to allow for air to be “spilled” by the inlet. The resultant shape of the projected/offset cowl and the projected compression surface leading edge is the STECI aperture.

Abstract: A diverterless hypersonic inlet (DHI) for a high speed, air-breathing propulsion system reduces the ingested boundary layer flow, drag, and weight, and maintains a high capture area for hypersonic applications. The design enables high vehicle fineness ratios, low-observable features, and enhances ramjet operability limits. The DHI is optimized for a particular design flight Mach number. A forebody segment generates and focuses a system of multiple upstream shock waves at desired strengths and angles to facilitate required inlet and engine airflow conditions. The forebody contour diverts boundary layer flow to the inlet sides, effectively reducing the thickness of the boundary layer that is ingested by the inlet, while maintaining the capture area required by the hypersonic propulsion system. The cowl assembly is shaped to integrate with the forebody shock system and the thinned boundary layer region.

Abstract: An advanced aperture inlet (AAI) uses a three-dimensional, mixed compression inlet design derived from computational fluid dynamics (CFD) by streamline tracing a supersonic section from an axisymmetric mixed compression inlet solution. The axisymmetric design is used to obtain a CFD solution with slip wall boundaries at the inlet design point and serves as a flow field generator for the AAI. The AAI geometry is obtained by projecting a desired aperture shape onto a surface model of the external oblique shock. Streamline seeds are located on the projected aperture segments and transferred into the CFD solution space. The streamlines generated by these seeds inside the CFD solution space are then used as a wireframe to define the supersonic diffuser back to the throat location. Traditional design techniques are then used to define the subsonic diffuser from the inlet throat to the engine face.

Abstract: A boost power converter for powering a load with an AC source is disclosed. The boost power converter comprises an AC to DC conversion circuit, a resonator, and a boost circuit. The resonator includes an energy storage device and a resonant circuit, and alternately applies energy from the energy storage device to the resonant circuit for powering the load. The AC to DC conversion circuit generates a DC signal in response to the AC source. The boost circuit includes a choke for receiving the DC signal, a rectifier for electrically coupling the choke to the energy storage device, and a switching device for selectively coupling the choke to the resonant circuit for charging and discharging the choke. The resonator operates in full resonant mode with zero voltage switching. The boost power converter is well-suited for ballast applications that drive a fluorescent lamp.