Vortex Flow Meter Principle of Operation

Under certain conditions vortices regularly form downstream of an object (bluff body) placed in a flowing fluid and shed on alternating sides of the stream. This phenomenon is commonly called a Karmen vortex street. The resultant vortex frequency is proportional to the fluid velocity and hence the flow rate can be calculated by counting the number of vortices being produced. This is achieved placing a pressure transducer, thermistor, or ultrasonic sensor just behind the bluff body which picks up the high and low pressure and velocity fluctuations as the vortices move past the sensor.

Vortices will not be shed regularly in medium to high viscosity fluids. Typically, a minimum Reynolds number of 10,000 is required to obtain optimum performance from a vortex flow meter.

Vortex Meter Overview

Vortex meters are versatile flow meters that have been gaining wider acceptance in recent years for measuring flow of liquids, gases or steams, mainly as an alternative to differential pressure flow meters. Vortex flow meters are applicable to a wide range of process temperatures, including high temperature flow applications; they are available in line sizes up to approximately 400 mm, with insertion vortex flow meters available for even larger pipe sizes.
View our range of Vortex flow meters
Use our product comparison tables for both industrial and compact vortex flow meters to guide you in selecting the right product for your needs.

Vortex Meter Advantages

  • Vortex meters can be used for liquids, gases and steam
  • Low wear (relative to turbine flow meters)
  • Relatively low cost of installation and maintenance
  • Low sensitivity to variations in process conditions
  • Stable long term accuracy and repeatability
  • Applicable to a wide range of process temperatures
  • Available for a wide variety of pipe sizes

Vortex Flow Meter Limitations

  • Not suitable for very low flow rates
  • Minimum length of straight pipe is required upstream and downstream of the vortex meter

NB.Vortex meters require sizing according to the flow rate being measured

Vortex flow meters are suitable for a variety of applications and industries but work best with clean, low-viscosity, medium to high speed fluids. Some of the main uses include:

  • Custody transfer of natural gas metering
  • Steam measurement
  • Flow of liquid suspensions
  • General water applications
  • Liquid chemicals & pharmaceuticals

Need Advice About Vortex Flow Meters?

iCenta is a instrumentation and control solution specialist with experience in control technologies for diverse applications, fluid types and process conditions. Call iCenta now for advice, sales & technical information on 01722 439 880.