Advanced Propulsion and Power Concepts for Large Size Class Unmanned Aerial Systems (UAS)

ABSTRACT:This phase II proposal outlines the necessary innovative technologies that define a revolutionary hybrid turbo-compound hyper bar 2-cycle aero-diesel engine. Technical breakthroughs in multi-fuel combustion supported by innovative high speed pneumatic fuel injection combined with catalytic hot surface ignition systems enable complete freedom of compression ratio essential for effective turbo-compounding. Scavenge air and on demand engine manifold boost pressure is supplied by an electrically assisted, combustion driven hyper bar turbocharger that eliminates the weight and bulk of a positive displacement blower. The high speed permanent magnet motor/generators are independently mounted to the high speed turbochargers as well as the axial gap motor/generator imbedded in the flywheel. The speed differential and turbo compounding is by means of electronic inverter control, thus eliminating the complexity of mechanical transmissions. Variable ratio exhaust valve results in a trapped range from 9-12:1 CR. without compromising the combustion chamber geometry. With the valve closed, the higher 12:1 compression ratio improves cost start, efficient part load and stable combustion during high altitude descent avoiding ignition flame out. This innovative combine cycle engine can be characterized as having the breathing capacity and power density of the gas turbine combined with the fuel economy of the direct injected diesel.BENEFIT:Advanced heterogeneous multi-fuel combustion with favorable peak to mean pressure ratio essential for lightweight and durable engine construction. -Self-running advanced hyper bar turbocharger technology with electrically assisted compressor and on demand combustion driven supercharge independent of main engine exhaust flow. -Maximum hybrid core engine power densities below 1lb/hp. double the peak takeoff power by electrically assisted supercharging and/or direct 50% power contribution from the brushless PM motor. extended UAS range and endurance from an efficient direct injected heterogeneous charge. low noise propulsor for covert missions. Commercial benefits: - lightweight, multi-fuel hybrid propulsion system suitable for all aspects of ground, marine and aviation segments in need of improved propulsion system efficiency.