Tumble Motion Evolution for GDI Engine using Particle Image Velocimetry (PIV) / Mohammed EL-Adawy ... [et al.]

In internal combustion engines (ICE), the intake generated flows are known to
have a fundamental influence on the combustion both in spark ignition (SI) and
compression ignition (CI) engines. The present study illustrates an
experimental study on the airflow inside the cylinder of a gasoline direct
injection (GDI) engine under steady-state conditions using particle image
velocimetry (PIV). PIV measurements were conducted through the central
vertical tumble plane, passing through the middle of the cylinder. The results
illustrate how the flow direction was transferred from reverse tumble motion
at low valve lifts to normal tumble motion at high valve lifts with nondimensional rig tumble of -0.23 and 0.69 at valve lift 1 and 9 mm respectively.