Technical Paper
Combustion and Heat Transfer Studies in a Spark-Ignited Multivalve Optical Engine
1990-02-01
900353
The application of sophisticated analytical techniques for the design of spark-ignition engines has brought about the need for detailed information on the heat transfer processes in these engines. This study utilized time-resolved heat-flux measurements, heat-release analysis and high-speed flame photography to investigate experimentally the combustion and heat-transfer characteristics of an optically accessible single-cylinder engine. The engine has a pent-roof shaped combustion chamber with two intake and two exhaust valves. The primary engine variable examined was the intake-flow configuration which was varied by means of shrouded valves. The measured local heat-flux histories on the combustion side of the head were found to have significant cycle-to-cycle and spatial variations, which are believed to be caused primarily by corresponding variations in combustion.