Vortex Flow Meter

The vortex flow meter is a velocity-type flow meter based on the Karman vortex principle. As fluid passes a triangular prism (bluff body) in the pipe, vortices are shed alternately along two lines; a piezoelectric crystal detects their frequency, which depends on the prism size and the flow velocity but not on medium properties such as temperature or pressure. From this frequency the meter calculates volume flow, and with density it gives mass flow. Integrated temperature and pressure compensation allows accurate measurement of liquids, gases and saturated or superheated steam at temperatures up to 350 °C.

Features

• Integrated pressure and temperature compensation
• Wide medium temperature range, up to 350 °C
• No moving parts and no wearing parts inside
• Fully welded SS304 body, SS316 selectable
• Accuracy ±1.5% standard, ±1.0% optional
• 4–20 mA, pulse, RS485/Modbus, HART and Profibus outputs
• Sizes DN15 to DN300 in flange, wafer, insertion and sanitary clamp versions
• Compact or remote converter, with or without local display and battery power

How it works

• Vortex frequency F = Sr × v × (1 − 1.27 d/D), where Sr is the Strouhal number, v the velocity, d the prism width and D the meter bore
• Volume flow Q = 3600 × F / K, where K is the meter coefficient in pulses per m³
• Mass flow M = Q × ρ, using the fluid density

Benefits

• Low maintenance and reliable operation

Applications

• Saturated and superheated steam
• Industrial gases and liquids
• Industrial water and cooling water
• Rotating industrial machinery lubrication
• Paper and pulp slurries
• Petroleum, chemical and fuel management

LKS supplies the Bont vortex flow meter in Malaysia, with installation, calibration and after-sales support. Contact our engineers for sizing and a quotation.