Velocity Flowmeters

Velocity flowmeters are popular because they give a direct measure of fluid velocity, the characteristic most commonly associated with flowrate. These flowmeters, however, are among the most sensitive to process conditions.

Turbine & Paddlewheel

Turbine meters and paddlewheel meters are among the most versatile flowmeters.

Advantages

  • One meter can be manufactured to handle a wide range of flowrates.
  • Turbine meters are highly accurate.
  • Low cost.
  • May be constructed of a variety of materials to handle a variety of fluids.
  • Paddlewheels provide a more cost-effective alternative when less accuracy is required or with viscous flow.
  • Low mass of rotor allows rapid response and ability to measure pulse flow.

Disadvantages

  • Can cause large pressure drops.
  • Flashing or bubble formation may occur if the downstream pressure of a liquid stream is too low.
  • Require lengths of straight pipe upstream and downstream.

Read -