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 demon strated with examples given for two- and four-valve cylinder heads. Th e optical methods used in this study comprise laser-induced fluorescen ce (LIF) to image the unburned mixture within the laser light sheet il luminating a plane of the combustion chamber and flame photography to visualize flame propagation. Simultaneous recording of engine thermody namic data allows the comparison of conventional engine diagnostics wi th the results gained from the optical techniques.