Types of flow meters and it's working principle. Advantages and disadvantages of each application wise

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Flow meters measure the flow rate of fluids or gases. There are various types with different working principles.

Differential Pressure Flow Meters: Measure flow by creating a pressure drop across an obstruction in the flow path (e.g., Orifice Plate, Venturi Tube). Advantages: Simple design, low cost. Disadvantages: Pressure loss, limited turndown ratio.
Positive Displacement Flow Meters: Measure flow by dividing the fluid into known volumes and counting them (e.g., Piston, Oval Gear). Advantages: High accuracy, suitable for low flow rates. Disadvantages: Limited turndown ratio, susceptible to wear and tear.
Turbine Flow Meters: Measure flow by the rotation of a turbine placed in the fluid stream. Advantages: Wide flow range, good accuracy. Disadvantages: Requires clean fluids, sensitive to fluid properties.
Electromagnetic Flow Meters: Measure flow by applying a magnetic field and measuring the induced voltage (e.g., Faraday's Law). Advantages: No moving parts, suitable for conductive fluids. Disadvantages: Limited accuracy at low flow rates, high cost.
Ultrasonic Flow Meters: Measure flow by transmitting and receiving ultrasonic waves through the fluid. Advantages: No pressure loss, suitable for various fluids. Disadvantages: Limited accuracy in non-ideal conditions, high cost.

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