Views: 50 Author: Site Editor Publish Time: 2025-05-22 Origin: Site
Flow meters are categorized based on their measurement principle, Flow meters types, and application requirements, below is a detailed classification:
| No. | Measurement Principle | Principle | Types | Applications | Reference Picture |
| 1 | Differential Pressure(DP) Flow Meters | Differential pressure (DP) flow meters calculate fluid flow based on the pressure drop created by a restriction in the flow path, usually an orifice or venturi plate. This pressure drop is directly related to the fluid's velocity and, therefore, its flow rate. The principle relies on Bernoulli's equation, which states that as a fluid's velocity increases, its pressure decreases. | Orifice Plate Venturi Tube Flow Nozzle Pitot Tube | Steam, gas, and liquid flow in pipelines |  |
| 2 | Positive Displacement(PD) Flow Meters | Positive Displacement (PD) flow meters work by measuring fluid flow by trapping and displacing fixed, measurable volumes of fluid. They do this by using internal mechanisms like gears, pistons, or discs to create chambers that fill and empty with the fluid. | Oval Gear Nutating Disc Piston Meter | High-viscosity liquids (oil, fuel), custody transfer |  |
| 3 | Velocity Flow Meters | Velocity flow meters measure fluid flow by detecting the speed of the fluid, rather than the amount of fluid passing through a point. They rely on principles like Faraday's Law, the Doppler Effect, or measuring the time it takes for a signal to travel through the fluid. | Vortex Flow Meter | Water, chemicals, compressed air |    |
| 4 | Mass Flow Meters | Mass flow meters directly measure the mass of a fluid passing through a system per unit time, rather than the volume, and typically operate by utilizing various principles like thermal, Coriolis, or ultrasonic technologies. Unlike volumetric flow meters, mass flow meters provide a more accurate measurement of the quantity of molecules in the fluid flow, regardless of pressure or temperature fluctuations. | Oil & gas, pharmaceuticals, food processing. |   | |
| 5 | Open Channel Flow Meters | Open channel flow meters primarily work by measuring either the liquid level (head) or the velocity and area of the flow, then calculating the flow rate using the appropriate formula. This can be achieved through various methods, including using ultrasonic sensors, microwave or radar technology, or primary devices like weirs and flumes. | Ultrasonic Level Sensor +Weir/Flume Area-Velocity Meters | Wastewater, irrigation. |  |
