Vortex flow meters work by placing a strategic obstruction in the path of the flowing media. This obstruction is commonly called a bluff body. As the gas or liquid passes by, vortices are created. They form on either side and break away in an alternating pattern.
A good example of this type of behavior in everyday life is a flag that is attached to a flagpole. As the flowing wind contacts the flagpole, the flagpole itself creates the obstruction that causes the flag to billow in the wind in an alternating wave. Another example is a rock in the middle of a river. It is plain to see, via the eddy behind the rock and the subsequent flow, that vortices are being created by the rock.
In the formed vortices, pressure decreases when a vortex is formed and increases when it is shed. This is true on both sides of the bluff body and causes pressure pulsations. The frequency of the pressure pulsations is directly proportional to the flow rate. A sensing element picks up the shifts from side to side behind the bluff body, amplifies the signal, and converts it to a 4-20 mA signal.
Vortex shedding flow meters come in a variety of line sizes, connections, material builds, and installation options. There are different models that are suitable for a wide variety of media including liquids, gases, and steam. Certain models also offer multi-variable capabilities. They all operate on the same principle of the bluff body obstruction into the flow stream.
For large pipe diameters, inline installations are not cost effective. Insertion vortex flow meters are an ideal solution for vortex flow measurement in larger pipes. They are installed by creating a hole in the process pipe with a connection and then inserting the probe into the hole via the connection on the meter. For insertion vortex flow meters, the probe should be inserted into the highest velocity part of the flow stream in the pipe.
Multi-variable vortex flow meters do not just measure the flow rate. They also employ temperature and pressure measurement to deliver a mass flow rate for gases, liquids, or steam. Because so many process parameters are being measured at one exact point in the process line, they can deliver a much more accurate measurement than stand-alone flow meters. Having three different types of measurement in one instrument saves money and decreases the complexity of installation and maintenance. KOBOLD carries the DVE Insertion Multi-Variable Vortex Flow Meter and the DVH Multi-Variable Flow Meter with inline installation capabilities through ANSI Flanged or Wafer-Types. Multi-variable vortex flow meters can deliver mass flow measurements.
KOBOLD Instruments has been manufacturing vortex flow meters for decades and offers a wealth of experience in choosing the correct vortex flow meter for your application. We offer both insertion and inline models as well as multi-variable vortex flow meters. We also offer a completely unique flow meter technology that is very similar to vortex flow meters. Model DOG is built especially for wet gas flow measurement and has a simple and reliable gravity-fed method to drain any liquid condensate. To learn more about this unique technology, view our DOG Oscillation Flow Meter product page. To see all of our vortex flow meters, visit our vortex flow meter product page.
Learn more about why you should partner with KOBOLD for your application.
Liquid, Gas, or Steam | Fully Welded Sensor | Optional Integral Temp/Pressure | Field Configurable | Up to 1,450 PSI | Up to 24" Lines
Liquid, Gas, or Steam | Fully Welded Sensor | Optional Integral Temp/Pressure | Field Configurable | Up to 1,450 PSI | Up to 8" Lines | ANSI Flanges or Wafers
For Liquids | Economical | Fixed or Rotatable Connections | PPS Body with SS or Brass Connections | Up to 26 GPM | Up to 290 PSI | Up to 176 °F | NPT Threads
KOBOLD USA is a subsidiary of KOBOLD Messring GmbH, a world-leading instrumentation engineering business founded in Germany in 1980 by Klaus J. Kobold. With patented technology and superior service, the company quickly established itself as one of the global leaders in sensor and control systems with high quality products. The KOBOLD brand name became synonymous with superior quality and technological advancement in instrumentation engineering.