Date: Around 1993
What is Cavitation?
I assume that you mean "cavitation" as used in fluid dynamics.
Cavitation is defined as the process of formation of local cavities is a
liquid, as a result of the reduction of pressure below a critical value,
called "vapor pressure." The most common occurrence of cavitation is in
propellers, both in water and air. In the case of a ship propeller, it
reduces the propulsive force quite a bit. It also can cause severe damage to
the propeller itself. On cavitation, bubbles of vapor start to appear in the
water. This creates an area of extreme low pressure on the propulsion side
of the propeller. As the pressure of the surrounding water rises again, the
vapor bubbles implode, and the water rushes in toward the propeller very fast.
Because the forces are very high and very concentrated, damage to the
propeller is likely. This same principal is true for pumps, hydraulic
turbines, or anything that is used to create pressure differences in a fluid.
The results of cavitation are less severe in some fluids than others,
depending upon the value of its vapor pressure.
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Update: June 2012