Vortex Shedding Technology
Measures flow using vortices generated by a stationary bluff body inside the pipeline.
Flow Meters
Vortex Flow Meter
Reliable Flow Measurement Using Vortex Shedding Technology
Flow Measurement Through Vortex Shedding
The FlowDo Vortex Flow Meter determines process flow by detecting alternating vortices generated as fluid passes a specially designed bluff body within the measuring section. The resulting vortex frequency is processed by the transmitter to determine the corresponding flow value.
VORTEX SHEDDING
Principle
NO ROTATING TURBINE
Sensing
PROCESS FLOW
Measurement
INLINE
Installation
Product Overview
Vortex Shedding for Industrial Flow Measurement
The FlowDo Vortex Flow Meter uses the vortex-shedding principle for industrial process-flow measurement.
Inside the meter, the process fluid passes around a stationary obstruction known as a bluff body. As the fluid moves past this obstruction, alternating vortices form downstream.
Within the applicable operating region, the frequency of these vortices is related to fluid velocity. A sensing system detects the vortex activity, and the transmitter electronics process the signal to determine the corresponding flow value. Unlike turbine flow meters, vortex measurement does not require a rotating turbine rotor.
Selection Guidance: Final product selection should consider process fluid, minimum/normal/maximum flow, pipe size, pressure, temperature, density where relevant, process connection, required output and installation conditions.
Key Engineering Principles
- Stationary bluff body generates alternating Kármán vortex streets downstream
- Vortex shedding frequency ($f$) directly relates to fluid velocity ($v$)
- Eliminates mechanical rotating elements, bearings, and rotating wear components
- Applicable for compatible liquid, gas, or steam processes based on selected model
- Digital transmitter converts periodic sensor pulses into rate and totalized flow
- Rugged flanged or wafer inline body engineered for industrial process pipelines
Instrumentation Capabilities
Key Features
Engineered for dependable flow sensing across industrial utility and process piping systems.
No Rotating Turbine
Flow measurement does not depend on a mechanical turbine rotor or moving bearing components.
Continuous Flow Measurement
Provides continuous process-flow information within the supported operating range.
Electronic Signal Processing
Detected vortex activity is electronically processed into a usable flow value by the transmitter.
Digital Display
Applicable configurations provide local digital indication of momentary rate and volume.
Process Output
Supported transmitter configurations provide 4–20 mA, pulse, or digital signals for control.
Industrial Construction
Designed with robust materials for compatible industrial process-flow applications.
Configurable Process Connection
Available configurations can be selected according to pipeline standards and pressure classes.
Operational Advantages
Reliable Vortex-Based Process Flow Measurement
Engineered for dependable industrial service without mechanical wear in the measuring stream.
No Turbine Rotor
No rotating turbine measurement element is required, eliminating mechanical rotor wear in compatible media.
Direct Flow Response
Vortex frequency responds directly to fluid velocity within the supported measurement region.
Local Visibility
Applicable transmitter configurations provide local digital flow and totalized volume indication.
Process Integration
Supported outputs can transmit flow information directly to plant indicators, PLCs, and control systems.
Multiple Process Applications
Vortex technology can be considered for suitable liquid, gas and steam applications depending on model configuration.
Automation Ready
Compatible transmitter outputs integrate seamlessly with industrial monitoring and telemetry skids.
Technical Configuration
Product Specifications
Comprehensive technical specification architecture for FlowDo Vortex Flow Meters.
Brand / Manufacturer
FlowDo
Product Name
FlowDo Vortex Flow Meter
Primary Category
Flow Meters
Product Type
Industrial Vortex Flow Meter
Measurement Principle
Vortex Shedding (Kármán Vortex Street)
Measured Parameter
Process Flow
Nominal Line Size
According to selected model / pipeline diameter
Flow Range
According to selected size and application
Minimum Flow Rate
According to selected model / fluid condition
Maximum Flow Rate
According to selected model
Accuracy
According to selected model
Repeatability
According to selected model
Supported Medium
Compatible liquids, gases, or steam according to selected configuration
Viscosity Limit
According to selected model / application guidance
Operating Reynolds Number
According to selected model specification
Sensor Technology
According to selected model (e.g. piezoelectric / balanced differential sensor)
Meter Body Material
According to selected configuration
Bluff Body Material
According to selected configuration
Wetted Materials
According to selected configuration
Process Connection Type
Flanged or wafer (according to selected model)
Pressure Rating
Model dependent
Display
According to selected configuration (digital display available)
Analog Output
According to selected configuration (e.g. 4–20 mA)
Pulse / Frequency Output
According to selected configuration
Digital Communication
According to selected configuration (e.g. RS485 Modbus / HART where supported)
Power Supply
According to selected configuration
Process Temperature
Model / application dependent
Ambient Temperature
According to selected transmitter model
Enclosure Protection
According to selected configuration
Primary Application
Industrial Process Flow Measurement
Final Technical Specifications Note: Final specifications depend on the selected FlowDo Vortex Flow Meter model, process medium (liquid, gas, or steam), pressure rating, and operating temperature. Contact FlowDo application engineering for technical selection.
Measuring Element
The Bluff Body Creates the Vortex Pattern
The bluff body is a stationary element positioned in the flow stream. Its geometry creates the alternating vortices required for the vortex-shedding measurement principle.
Mechanical Design
No Rotating Turbine Measurement Element
Unlike a turbine flow meter, vortex measurement does not rely on a rotating rotor to determine flow. The bluff body remains stationary while the sensing system detects vortex activity generated by the moving process fluid.
- No rotating turbine rotor: Eliminates delicate moving vanes in the fluid path
- No rotor bearings: Avoids mechanical bearing wear and bearing friction errors
- Broad medium compatibility: Suitable for compatible liquids, gases, and steam
- Rigid pipeline design: Robust mechanical structure suited for high process pressures
Signal Detection
Detecting the Vortex Pattern
The selected Vortex Flow Meter uses a sensing system to detect the periodic pressure pulses or micro-deflections created by vortex shedding. The transmitter converts the detected signal into usable flow information.
Sensor Technology: Sensing technology (such as piezoelectric sensors or balanced differential elements) is configured according to the selected FlowDo model and process medium requirements.
Process Media
Process Media Suitability: Liquid, Gas & Steam
Vortex shedding operates across diverse fluid states, provided density, velocity, and process parameters meet the selected model criteria.
Liquid Media
Liquid Flow
Vortex technology can be used for compatible liquid applications when the selected meter's flow, density, viscosity, pressure and temperature requirements are satisfied.
Availability depends on selected configuration.
Gas Media
Gas Flow
Suitable Vortex Flow Meter configurations can be used for compatible gas-flow applications when process conditions meet the selected meter specification.
Availability depends on selected configuration.
Steam Media
Steam Flow
Vortex flow measurement is commonly considered for suitable steam applications, but the selected meter must be appropriate for the actual steam pressure, temperature and measurement requirement.
Availability depends on selected configuration.Steam Conditions Matter
Steam metering requirements differ significantly between steam states:
- Saturated Steam: Pressure and temperature are directly coupled along the saturation curve.
- Superheated Steam: Steam temperature is elevated above the saturation temperature at the given pressure.
The required measurement architecture depends on whether volumetric flow, compensated flow, mass flow, or energy measurement is required.
Volumetric Flow and Mass Flow Are Different
Volumetric Flow: Volume passing through the pipeline per unit time (e.g. m³/h, L/min).
Mass Flow: Mass passing through the system per unit time (e.g. kg/h, t/h).
A standard vortex measurement does not automatically mean mass-flow measurement. For compressible media like steam and gas, mass-flow calculation requires density information and appropriate compensation depending on the application and transmitter configuration.
Compensated Measurement
When Temperature and Pressure Compensation Are Required
For gases and steam, density varies dynamically with process temperature and line pressure.
VORTEX FLOW SIGNAL
+ TEMP / PRESSURE INPUT
→ COMPENSATED MASS FLOW
In compressible gas and steam lines, fluctuations in operating pressure and temperature alter fluid density. Where compensated mass flow is required, external or supported transmitter inputs incorporate temperature and pressure measurements to compute true dynamic mass or energy flow.
Note: Specific compensation capability depends on the selected FlowDo model and transmitter architecture.Meter Sizing
Select the Meter Around the Actual Flow Range
Vortex meters require sufficient flow conditions for stable vortex formation and detection. Selection should consider minimum, normal and maximum process flow rather than pipe size alone.
Flow Velocity & Range
Meter sizing should be based on actual flow velocity across minimum, normal, and maximum conditions to ensure the vortex shedding frequency remains in the linear measurement zone.
Very Low Flow Requires Application Review
Stable vortex measurement requires suitable process velocity. Very low-flow conditions may fall below the reliable vortex-shedding threshold of a selected meter size.
Flow Conditions Influence Vortex Formation
Vortex behavior depends on fluid density ($\rho$), velocity ($v$), characteristic diameter ($D$), and viscosity ($\mu$), governed by Reynolds number ($Re = \frac{\rho v D}{\mu}$).
Stable Upstream Flow Supports Reliable Measurement
Elbows, valves, reducers, pumps and other piping components can disturb the velocity profile entering a Vortex Flow Meter. Follow the upstream and downstream straight-run requirements specified for the selected FlowDo model.
Follow the Meter Flow Direction
Install the meter according to the flow-direction arrow marking on the meter body to ensure fluid impacts the leading face of the bluff body properly.
Consider Mechanical Vibration
Because vortex measurement relies on detecting periodic flow pulses, excessive mechanical pipe vibration from nearby pumps or compressors can interfere with sensing. Pipe supports are recommended for vibrating lines.
Consider Pressure Loss & Process Limits
The bluff body creates a slight obstruction causing a minor pressure drop. Verify that the meter body, sensor materials, and flange connections match the process operating pressure and temperature.
Applications
Industrial Process Applications
Practical vortex flow measurement across steam distribution, compressed gases, and process liquids.
Steam Systems
Boiler header steam distribution and process steam monitoring where selected model is suitable.
Process Water
Clean utility water, cooling loops, and high-velocity fluid flow measurement.
Industrial Liquids
Compatible low-viscosity liquid measurement free from entrained slurries or large particles.
Compressed Air
Plant compressed air generation, audit lines, and distribution networks where supported.
Industrial Gas
Nitrogen, carbon dioxide, argon, and compatible non-corrosive gas pipelines.
Boiler Utilities
Feedwater lines and energy auditing in central boiler house installations.
Chemical Processing
Compatible chemical lines where wetted materials and temperature classes match.
Power Plants
Auxiliary steam monitoring, turbine bypass lines, and plant utility management.
HVAC & Utilities
District heating steam supply, hot water metering, and central facility utilities.
Fluid Suitability
Is a Vortex Flow Meter Right for the Application?
Evaluating when vortex shedding technology is an ideal fit versus when an alternative flow principle is recommended.
Good Application Fit
Compatible Process Conditions
- ✓ Suitable liquid, gas, or steam: According to selected model
- ✓ Moderate to high flow velocity: Operating within stable shedding range
- ✓ Low to moderate viscosity: Minimizing viscous dampening of vortices
- ✓ No moving turbine rotor: No mechanical wear in clean fluid stream
- ✓ Stable continuous flow: Well-supported piping without extreme vibration
Application Review Required
Alternative Technology Recommended
- ✕ Very low flow velocities: Vortex signal too weak for detection
- ✕ High-viscosity liquids: Heavy viscous drag dampens vortex shedding
- ✕ Heavy slurries or large solids: Particles can accumulate on bluff body
- ✕ Severe pipe vibration: Mechanical noise interferes with sensor
- ✕ Two-phase flow: Wet steam or gas bubbles distort vortex frequency
Another flow technology (such as FlowDo Electromagnetic, Turbine, or Ultrasonic Flow Meters) may be more appropriate when process conditions do not suit a stationary bluff body.
Technology Comparison
Vortex or Turbine Flow Meter?
Choosing between stationary bluff-body vortex shedding and rotor-based turbine flow measurement.
Vortex Flow Meter
- Measurement Principle
- Vortex shedding (Kármán vortex street).
- Primary Measuring Element
- Stationary bluff body.
- Rotating Parts
- No turbine rotor or rotor bearings.
- Process Media
- Compatible liquid, gas, or steam (model dependent).
- Important Considerations
- Minimum flow, vibration, piping conditions.
Turbine Flow Meter
- Measurement Principle
- Rotor rotation driven by fluid velocity.
- Primary Measuring Element
- Rotating turbine rotor with precision bearings.
- Rotating Parts
- Yes (rotor spins in fluid path).
- Process Media
- Compatible clean liquids according to model.
- Important Considerations
- Fluid cleanliness, viscosity, rotor/bearing condition.
Induction vs Shedding
Vortex or Electromagnetic Flow Meter?
Comparing vortex shedding with electromagnetic induction sensing.
Vortex Flow Meter
- Principle
- Vortex shedding.
- Medium
- Suitable liquid, gas, or steam depending on configuration.
- Conductivity
- Not inherently required by vortex principle.
- Internal Element
- Stationary bluff body.
Electromagnetic Flow Meter
- Principle
- Electromagnetic induction (Faraday's Law).
- Medium
- Electrically conductive liquids only.
- Conductivity
- Required.
- Internal Element
- Completely unobstructed bore; no bluff body, no rotor.
Technology selection depends on fluid properties, pipe size, flow range, pressure, temperature, installation and required measurement performance.
Acoustic vs Bluff Body
Vortex or Ultrasonic Flow Measurement?
Comparing inline vortex shedding with ultrasonic acoustic wave propagation.
Vortex Flow Meter
- Principle
- Vortex shedding.
- Installation
- Typically inline for this product class.
- Internal Element
- Stationary bluff body.
- Important Conditions
- Stable vortex formation and installation conditions.
Ultrasonic Flow Meter
- Principle
- Sound-wave propagation / transit time.
- Installation
- Inline or clamp-on depending on model.
- Internal Moving Parts
- No.
- Important Conditions
- Pipe, fluid and acoustic requirements depend on technology.
Three-Technology Comparison
Compare Vortex, Turbine & Electromagnetic Technologies
Understanding when each industrial flow measurement principle is best considered.
Vortex Flow Meter
- Principle
- Vortex shedding.
- Rotating Parts
- No.
- Conductivity Required
- No inherent requirement.
- Typical Medium
- Model dependent (liquid, gas, steam).
- Main Selection Concern
- Minimum flow velocity, vibration, piping conditions.
Turbine Flow Meter
- Principle
- Rotor rotation.
- Rotating Parts
- Yes.
- Conductivity Required
- No inherent requirement.
- Typical Medium
- Compatible clean liquids.
- Main Selection Concern
- Fluid cleanliness, viscosity, bearing wear.
Electromagnetic Flow Meter
- Principle
- Electromagnetic induction.
- Rotating Parts
- No.
- Conductivity Required
- Yes.
- Typical Medium
- Conductive liquids / slurries.
- Main Selection Concern
- Conductivity, liner & electrode compatibility.
No single flow-meter technology is ideal for every application.
System Integration
From Vortex Detection to Process Monitoring
Converting periodic vortex frequency into analog signals, totalized volume, and remote telemetry.
FlowDo Vortex Flow Meter
Fluid Velocity Drives Vortex Shedding Frequency
↓
Sensor Pickup & Preamplifier
Micro-Pressure Pulse Detection • Frequency Signal
↓
Transmitter Electronics
4–20 mA Current Loop • Scaled Pulse Output • Digital Display
↓
Local Process Indicator / Totalizer
FlowDo FDI-96 Digital Flow Indicator / Panel Meter
PLC / DCS Control System
Process Flow Feedback, Burner Control & Energy Logs
↓
FlowDo IoT Cloud & Telemetry
Live dashboards, steam usage audits, historical logs & automated alarms
Product Configuration
Configure the Vortex Flow Meter for Your Process
Provide key process parameters to identify a suitable FlowDo Vortex Flow Meter configuration.
Process Medium
Liquid, gas, or steam composition and fluid state.
Pipe Size
Nominal pipeline diameter and connection standard.
Flow Range
Minimum, normal, and maximum operating flow rates.
Process Pressure
Operating and maximum design pressure.
Process Temperature
Operating and maximum temperature conditions.
Density & Viscosity
Fluid properties under operating conditions where relevant.
Process Connection
Flanged (ANSI/DIN/JIS) or wafer installation style.
Body & Wetted Material
Selected according to chemical compatibility requirements.
Output & Communication
4–20 mA, pulse, or digital communication interface.
Compensation Requirement
Volumetric flow vs. temperature/pressure compensated mass flow.
Instrumentation Ecosystem
Related Flow Measurement Products
Explore complementary FlowDo flow meters and panel indication instruments.
Electromagnetic Flow Meter
Industrial electromagnetic flow meter for accurate volumetric measurement of conductive liquids with zero moving parts.
View details & specs →
Turbine Flow Meter
Industrial turbine flow meter for responsive volumetric flow measurement of compatible clean liquids using precision rotor mechanics.
View details & specs →
Digital Flow Indicator
FDI Series High-accuracy panel meter for displaying instantaneous flow rates and totalized volume from compatible pulse and 4–20 mA inputs.
View details & specs →Frequently Asked Questions
Vortex Flow Meter FAQs
Answers to common technical questions regarding vortex shedding flow measurement.
What is a Vortex Flow Meter?
A Vortex Flow Meter measures flow by detecting alternating vortices generated as process fluid passes a stationary bluff body.
What is vortex shedding?
Vortex shedding is the alternating formation of vortices downstream of an obstruction placed in a moving fluid.
What is a Kármán vortex street?
It is the repeating pattern of alternating vortices formed downstream of a suitable bluff body.
How is flow determined?
Within the meter's applicable operating range, vortex frequency is related to fluid velocity. The transmitter processes this detected frequency into a flow value.
Does a Vortex Flow Meter have a turbine?
No. Vortex measurement uses a stationary bluff body rather than a rotating turbine rotor.
Can it measure liquids?
Suitable FlowDo Vortex configurations can be used for compatible liquid applications when the process conditions meet the meter specification.
Can it measure gases?
Gas measurement depends on the selected FlowDo Vortex configuration and process conditions.
Can it measure steam?
Vortex technology is commonly used for suitable steam applications, but steam compatibility and operating limits must be verified for the selected FlowDo model.
Can it measure mass flow?
Standard vortex measurement does not automatically mean mass-flow measurement. Mass-flow calculation may require density and temperature/pressure compensation depending on the process and transmitter configuration.
Does it support temperature compensation?
Temperature compensation should only be listed where confirmed for the selected FlowDo configuration.
Does it support pressure compensation?
Pressure compensation should only be advertised where confirmed.
Can it provide 4–20 mA?
4–20 mA should only be shown for configurations confirmed to support it.
Does it support HART or Modbus?
Communication protocols should only be shown where confirmed by actual FlowDo technical documentation.
Why does minimum flow matter?
Vortex measurement requires suitable flow conditions for stable vortex formation and detection, so minimum flow is an important meter-selection parameter.
Does pipe vibration affect measurement?
Excessive mechanical vibration can affect vortex detection depending on the meter design and installation.
Why are straight pipe runs important?
Upstream flow disturbances can affect the flow profile entering the meter. Follow the straight-run requirements for the selected FlowDo model.
How is Vortex different from Turbine?
Vortex meters detect vortices created by a stationary bluff body, while turbine meters measure flow using a rotating rotor.
How is Vortex different from Electromagnetic?
Vortex measurement detects vortex shedding, while electromagnetic meters measure conductive-liquid flow using electromagnetic induction.
Can it connect to PLC or SCADA?
Yes, where the selected transmitter output or communication interface is compatible with the control system.
How do I select the correct Vortex Flow Meter?
Provide the process medium, pipe size, minimum/normal/maximum flow, pressure, temperature, density/viscosity where relevant, connection and required output.
Need Help Selecting a Vortex Flow Meter?
Configure the Right Vortex Flow Meter for Your Process
Share your process medium, pipe size, minimum/normal/maximum flow, pressure, temperature and required output with FlowDo to identify a suitable Vortex Flow Meter configuration.
For faster selection, provide: Process Medium • Pipe Size • Minimum Flow • Normal Flow • Maximum Flow • Process Pressure • Process Temperature • Density / Viscosity if relevant • Process Connection • Required Output • Compensation Requirement