Optical Research Engines—Tools in Gasoline Engine Development?

The paper describes the design of a single cylinder base engine which provides optical access to the combustion chamber via glass cylinders and a piston with a glass crown. The application of this engine to the visual analysis of gasoline mixture formation and combustion is demonstrated with examples given for two- and four-valve cylinder heads.

The optical methods used in this study comprise laser-induced fluorescence (LIF) to image the unburned mixture within the laser light sheet illuminating a plane of the combustion chamber and flame photography to visualize flame propagation. Simultaneous recording of engine thermodynamic data allows the comparison of conventional engine diagnostics with the results gained from the optical techniques.