Research On Performance Of FAI Two-Stroke Disi Engines Of Aerial Vehicles

Two-stroke engine has been widely used in the field of small and medium-sizedaerial vehicle due to its high mechanical efficiency, light weight, simple structure andhigh specific power. However, traditional two-stroke engine depends on mixturescavenging, which leads to fuel short-circuiting; it is reaching a key point for itssurvival due to its poor fuel economy. In recent years, with widely use of aerialvehicle, the demand for it becomes increasingly high. As a power system, high fuelconsumption of traditional two-stroke engine became a constraint for the developmentof aerial vehicle. GDI engine allows the introduction of the fuel separately from thescavenging air，theoretically, it is an effective way to eliminate the short-circuitingproblem, then greatly improve the fuel economy of two-stroke engine, and increasethe payload capacity and sailing distance.This paper research GDI technique applied to aerial two-stroke engine. First, theFAI fuel injection system used to GDI combustion is developed on the basis of thecarbureted aerial four cylinder engine, included new throttle body, cylinder head,combustion chamber, fuel system, ignition system, electronic control system andlubrication system, the main point is developed a set of GDI ECU applied totwo-stroke engine under four cylinder, including the design and development of itshardware, software and inductive ignition system which is controlled by ECU. Second,a prototype is manufacture, and build an engine test bench, the successful operation ofthe engine prove that the system designed achieve the desired function, the variouscomponents work reliable. Last, according to the experiment results analysis of theinfluence of injection advance angle, injection pulse and ignition advance angle onengine performance indicate that two-stroke GDI engine using FAI system canimprove engine performance, reduce fuel consumption and HC emissions.