Visualization of combustion processes of internal combustion engines

Very fast visualization of fuel injection and spray impingement on the wall, the laser ignition process, and auto-ignition of the end-gas region due to flame propagation during the engine knock cycle was demonstrated using an ultra-high-speed camera for a detailed understanding of the combustion process inside an internal combustion (IC) engine. The combustion process of an IC engine is complex, involving several thermal fluid phenomena. The high-speed video camera was an essential tool for visualizing and recording these high-speed phenomena. When more magnified images are needed, the ultra-high-speed camera and a long-distance microscope with a Barlow lens were used. Here, high-speed visualization techniques were shown to understand the combustion process inside an IC engine.