Lexmark International, Inc. has been my work home for the last 14 years. During this time I have built mathematical models, exercised and customized commercial and in-house computational fluid dynamics programs, and developed our ability to photograph the microscopic events of the inkjet ejection. Following are examples of flow visualizations from my simulations and experiments.

An ejection simulation with the Milagro 3-D code by Dr. Bob Clark with inkjet routines by David Weatherly. The latter includes the 1-D model that determines the evolution of the bubble pressure. The bubble pressure and the ink momentum interact to determine the volume and shape of the bubble, while heat conduction into the ink and phase change at the bubble wall determine the mass of vapor in the bubble. The visualization was produced with Fieldview.

An ejection simulation in which the meniscus film thins and breaks, venting the vapor bubble to atmosphere. The visualization was produced with Paraview.

Same ejection from a different viewpoint. Notice the jet break-up and satellite formation.

Ejection from an ejector with fresh ink. Note that the vapor bubble does not vent to atmosphere - the thin film of liquid between the meniscus and the bubble never breaks.

Ejection from same ejector after several seconds of idle time.

Nucleation, growth, and collapse of an inkjet vapor bubble in a channel. The liquid temperature reaches about 300 C within 1 microsecond of the start of heating. At onset of nucleation, the steam pressure is about 100 atmospheres. Collapse occurs within about 3 microseconds.

More video to follow.

Order:
Jet video 2 (mag)
PINPC bubble in jet (reduce size first)
YoC meniscus overshoot drainback (reduce size)
test=bubble73
Newman 090429
refill_15.8-16_Vulcaner (repeat, reduce size?)
movie08_01_09
movie08_01_09a
movie0001
movie1000