What type of flow do displacement meters measure?

• A. High industrial flows
• B. Low and intermediate flows, such as domestic use
• C. Flow during heavy rain events
• D. Flow rates of stormwater runoff

Answer: (B)

Displacement meters are designed to measure the volume of fluid that passes through them by utilizing a mechanism that displaces a known amount of water with each cycle. This makes them particularly effective for measuring low and intermediate flow rates, such as those found in domestic water use. They operate by capturing the movement of water as it enters the meter, commonly using a piston or a rotating chamber to represent the volume accurately.

The nature of displacement meters allows them to maintain accuracy at lower flow rates, which is why they are commonly used in residential settings where water usage tends to fluctuate significantly. As a result, their application is best suited for capturing household consumption patterns accurately, leading to their widespread deployment in domestic water metering. Their efficiency diminishes at very high flows or when conditions exceed their design specifications.