Flowmeters

Flowmeters

Flowmeters are devices used to measure the flow rate of a fluid, which can be liquid, gas or steam. They are commonly used in a variety of industries such as chemical, pharmaceutical, oil and gas, and water treatment. Flowmeters can be classified into different types based on the principle of operation, which include differential pressure, positive displacement, electromagnetic, ultrasonic, thermal, and vortex shedding. Differential pressure flowmeters work by creating a constriction in the flow path, which causes a pressure drop across the constriction. The pressure drop is proportional to the flow rate and can be measured using a differential pressure transmitter. Positive displacement flowmeters measure the volume of fluid passing through the flowmeter by trapping it in a chamber and counting the number of times the chamber is filled and emptied. Electromagnetic flowmeters use Faraday's law of electromagnetic induction to measure the flow rate of conductive fluids. Ultrasonic flowmeters measure the velocity of the fluid by transmitting and receiving ultrasonic waves through the fluid. Thermal flowmeters measure the heat transfer between a heated element and the fluid. Vortex shedding flowmeters measure the frequency of vortices shed by a bluff body placed in the flow path. The choice of flowmeter depends on the application requirements such as accuracy, rangeability, pressure and temperature limitations, and fluid properties. Flowmeters are widely used in process control systems to monitor and control the flow of fluids in pipelines, tanks, and reactors. They are also used in custody transfer applications to measure the quantity of fluids transferred between parties.

flow rate, differential pressure, positive displacement, electromagnetic, ultrasonic, thermal, vortex shedding

— Brian Wilson