This is a basically a type of Gear Pump but
with lobes instead of gears. The three-lobe gear pump, like the two-lobe
version, is commonly used to force high-pressure air into combustion compartments
of a diesel engine.
The output of these pumps is more pulsed than the output
of a gear pump because there are fewer teeth. The fluid is delivered in comparatively
larger packets.
Gases are compressible (whereas liquids basically are not),
therefore the three lobe and two lobe gear pumps work particularly well with gases,
since the compressibility helps smooth the flow.
(This is a 20-frame
animation, converted to animated GIF format and then super-compressed for Internet
transmission. (Note: On some Internet browsers it may be displayed much less smoothly
than the CD-ROM version, where the frames are timed to a thousandth of a second.))
