Wastewater New York State Practice Exam

What condition occurs in a pump due to low pressures, resulting in boiling water and potential damage to the impeller?

1. Cavitation

2. Compression

3. Vaporization

4. Condensation

The correct answer is: Cavitation

Cavitation is a phenomenon that occurs in a pump when the pressure of the liquid being pumped falls below its vapor pressure. Under these conditions, localized boiling can take place, creating vapor bubbles within the liquid. As these bubbles form and subsequently collapse or implode as they move into areas of higher pressure within the pump, they generate shock waves that can cause significant damage to the impeller and other components of the pump. This mechanical damage can lead to decreased efficiency, increased maintenance costs, and ultimately, pump failure if not addressed. Understanding this process is essential for those working with pump systems, as it highlights the importance of maintaining appropriate pressure levels and the need for careful design considerations in pump applications to mitigate the risk of cavitation. This is particularly relevant in wastewater management and treatment processes where varied fluid dynamics can lead to such conditions.