Orifice plates, venturi tubes, and nozzles are classified under which group?

Orifice plates, venturi tubes, and nozzles are classified under flow meters because they are devices specifically designed to measure the flow rate of fluids. These devices operate based on principles of fluid dynamics, utilizing the relationship between pressure drop and flow rate. For each type of device, as fluid flows through, the cross-sectional area changes, causing a change in velocity and pressure, which can be related to the flow rate.

While head meters and pressure meters may measure related properties, they do not directly capture the flow rate in the same way as the aforementioned devices. Head meters typically refer to devices that measure the height of a fluid column to determine pressure, while pressure meters focus on direct pressure measurements. Analog meters generally refer to instruments that provide continuous readings on a scale, many of which may not be directly linked to fluid flow measurements. Thus, the classification as flow meters is essential for understanding their functional purpose in fluid systems.