JM Harwood, LLC, and UAH Propulsion Research Center propose the development of an electronic miniature Direct Fuel Injection (DFI) system for 5-20 hp heavy fuel engines. This highly integrated Very Small Injection Technology (V-SInTech) DFI system will be capable of (a) multiple injections per cycle, (b) variable injection timing, (c) variable spray penetration depth, (d) real-time closed loop modification of injection timing to account for fuel properties, and (e) multi-fuel operation over a broad range of operating conditions. The proposed Phase I will expand the capability of a baseline V-SInTech DFI and ECU previously demonstrated. The V-SInTech DFI will produce fine atomization and precise control of the injection timing / fuel metering even at part-throttle conditions. The target engine for the Phase II demonstration of the V-SInTech DFI system is a heavy fuel, bolt-in replacement for the 3W-56 currently used in Honeywells g-MAV UAV. The proposed Phase I will conduct four tasks. These will include (1) quantifying the relationship between critical control parameters, design parameters, and injector performance; (2) characterizing the baseline injectors spray; (3) updating the baseline injector design, and (4) identifying required additions to the ECU architecture.
Benefit: The proposed activity will develop a miniature Direct Fuel Injection system which will solve the problem that has hamstrung heavy fuel engine development. The target engine is a heavy fuel, bolt-in replacement for the 3W-56 currently used in Honeywells g-MAV UAV. However, a slightly larger version of this DFI system could be used on the engine for the Small Tactical Unmanned Aircraft System/Tier II Unmanned Aircraft System (STUAS/Tier II UAS).
Keywords: V-SInTech DFI, V-SInTech DFI, Heavy Fuel Engine, STUAS/Tier II, Direct Fuel Injection, g-MAV
