| This project involved the custom assembly of a fuel and air management system for an experimental 1 cylinder two-stroke engine using a unique cylinder head and valve assembly. The engine's patented internal combustion cycle combines the action of a blower, used for the scavenging and intake cycle, with high-pressure gasoline direct injection (GDI) in the compression stroke. These features would allow a production model to be designed with a dedicated lubrication system like that of a four-stroke, essentially eliminating the traditional pollution associated with the two-stroke engine.; This thesis establishes proof of principle and reports the progress in the development and testing of this novel two-stroke GDI engine that incorporates uniflow scavenging without the use of camshaft actuated poppet valves. Scavenging flushes out the spent gases and introduces the new charge in a combustion chamber. Compressed air is fed into the cylinder through a matrix of passive check valves located in the cylinder head. The combination of air-only scavenging with high pressure GDI should ensure that traditional two-stroke pitfalls, such as high emissions and poor fuel economy due to short circuiting, are eliminated. The engine was successfully operated at speeds up to 5500 rpm. In-cylinder and intake plenum pressures were measured as a function of time and crank angle from which the check valve opening and closing time and the duration of the scavenging process was identified. |
