Multi-lane, bidirectional tunnel anemometer

The CROSSFLOW provides an open path, cross bore solution for measuring air velocity and direction in a tunnel.


Proven measurement
Proven ultrasonic transit time measurement technology
Atmosphere mesurement
Measurement independent of temperature, pressure and composition of the tunnel atmosphere
Easy integration
Choice of interface options enabling easy integration into tunnel control system
CROSSFLOW-T model with integrated temperature sensor
Optional extended warranty and 5 year refurbishment programs are available

See our technology in action.

Schedule a free demo to get a first-hand look at how our solutions support your business.


The CROSSFLOW is an open path, cross bore air flow monitor designed to measure air speed and direction in multi-lane and bidirectional tunnels. The system uses reliable ultrasonic transit time measurements between a pair of transceivers which are mounted and aligned on either side of the tunnel.

The CROSSFLOW is a self-contained, intelligent analyser with industry standard SCADA / PLC interface options including Current Outputs, Digital Relays and RS485 (Modbus RTU). The wall mounted alignment bracketry and quick lock cable plugs ensure the CROSSFLOW is easy to install and commission. With no moving parts the CROSSFLOW is very easy to maintain, there are no regular offline servicing requirements beyond an annual check and clean.


  • Rugged construction design to withstand corrosive tunnel atmospheres and regular tunnel washing
  • Pre-calibrated “Fit and Forget” transceiver
  • Prewired interconnecting cable and termination points saves time during the installation
  • No moving parts and low maintenance requirements
  • The CROSSFLOW is designed to tolerate high sided vehicles momentarily passing through the Ultrasonic signal path ensuring uninterrupted air flow readings.



Discover Acoem’s case studies

Find your solutions.

CROSSFLOW can also be paired with a TSCU operator interface (Acoem Control Unit), which is a remotely located control unit with a display, keypad and full range of interface capabilities to match those found in the CROSSFLOW itself. Since the TSCU has all the same interface abilities as the CROSSFLOW, interface connections can be made directly to the TSCU (which can be positioned at a convenient accessible location) and/or to the CROSSFLOW. This versatility offers the flexibility to accommodate a wide range of wiring schemes.

Request pricing

Connect with Acoem

Contact us to learn more about our solutions, services, and training programs.

Would you like to…?