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Sonic Nozzles

Sonic Nozzles2

What is a Sonic Nozzle?

A “sonic nozzle” (also known as “Critical Flow Venturi” or “Critical Flow Nozzle”) is a flow meter that can be used as a calibration standard for gas flow meters or any flow measurement device.

By design, sonic nozzles are a constant volumetric flow meter. However, with the use of a regulated pressure supply, the sonic nozzle becomes a “state-of-the-art” mass flow meter. Considering both the divergent section design and the flow rate, sonic nozzles may operate with an exit pressure as high as 90% of the inlet pressure.

Advantages of Sonic Nozzles

  • Internationally Recognized Flow Meters
  • Mass Flow Varies Linearly with Inlet Pressure
  • Minimum Upstream Piping Required
  • Long Term Accuracy
  • Excellent Repeatability
  • No Moving Parts
  • Differential Pressure Measurement Not Required
  • Flow Rate Is Not Affected by Downstream Flow Disturbances
  • Mass Flow is Constant with Varying Downstream Pressure

Common Sonic Nozzle Applications

  • Calibration of Gas Flow Meters
  • Gas Flow Metering
  • Calibration of Turbine Engine Component Gas Passages
  • Calibration of Automotive Component Air Passages
  • Measurement of Automotive Induction Air
  • Automotive Emissions Testing
  • Compressor Discharge Capacity Tests
  • Valve CV Tests
  • Flow Limiting
  • Over Speed Protection of Gas Flow Meters

Sonic Nozzles Supplied by DP-Flow Ltd

We supply a wide variety of sonic nozzles for use as standalone flow meters and as components in complete systems.