Cavitation is a phenomenon in which rapid changes of pressure in a liquid lead to the formation of small vapor-filled cavities, in places where the pressure is relatively low.
When subjected to higher pressure, these cavities, called “bubbles” or “voids”, collapse and can generate an intense shock wave
Cavitation is a significant cause of wear in some engineering contexts. Collapsing voids that implode near to a metal surface cause cyclic hrough repeated implosion. This results in surface fatigue of the metal causing a type of wear also called “cavitation”. The most common examples of this kind of wear are to pump impellers, and bends where a sudden change in the direction of liquid occurs. Cavitation is usually divided into two classes of behavior: inertial (or transient) cavitation and non-inertial cavitation.
Non-inertial cavitation is the process in which a bubble in a fluid is forced to oscillate in size or shape due to some form of energy input, such as an . Such cavitation is often employed in baths and can also be observed in pumps, propellers, etc.
Since the shock waves formed by collapse of the voids are strong enough to cause significant damage to moving parts, cavitation is usually an undesirable phenomenon. It is very often specifically avoided in the design of machines such as turbines or propellers, and eliminating cavitation is a major field in the study . However, it is sometimes useful and does not cause damage when the bubbles collapse away from machinery,
