A Photographic Study of Combustion and Knock in a Spark-Ignition Engine
A 1938 NASA technical report, A Photographic Study of Combustion and Knock in a Spark-Ignition Engine, issued for engineers and researchers studying engine combustion. The three plates are photographic strip sequences of high-speed film frames of flame fronts inside a spark-ignition engine cylinder, each row labelled with spark timing and fuel-air ratio values. Designers might take from them the stark black-and-white grid of repeated frames, with bright, irregular glowing shapes against dark fields, as a model for sequential motion studies.
