What is "cavitation" in hydraulic systems?

Cavitation refers to the formation and collapse of vapor bubbles in a hydraulic fluid when the pressure of the fluid falls below its vapor pressure, often due to rapid changes in velocity or pressure within the system. When these vapor bubbles collapse, they create shock waves that can lead to physical damage in components such as pumps and valves. This damage can manifest as pitting, erosion, or other forms of wear, ultimately resulting in reduced efficiency and potential failure of hydraulic systems.

The other choices describe phenomena or methods that do not pertain to cavitation. For example, the freezing of hydraulic fluid involves temperature changes rather than pressure dynamics. Introducing air into the system deals with air infiltration issues rather than vapor bubble dynamics. Lastly, cleaning techniques for hydraulic components do not involve the physical processes described by cavitation. Thus, the correct understanding of cavitation highlights the importance of maintaining proper pressure conditions within hydraulic systems to prevent such damaging occurrences.