Abstract
Spark tracing method was used to visualize the pattern of air flow induced into cylinder of a motored model engine, which consisted of a transparent plastic cylinder with an exhaust magnetic valve on its top.
The spark time lines of the air flow were photographed simultaneously by three cameras located on each direction, over-head, front and side.As the resilts, the pattern of air flow was found to be much affected by the positions of the piston(denoted by crank angle θ)and of the spark electrodes(β).
