No matter how challenging the application or site conditions, Teledyne Isco offers a proven technology for your needs.
AV sensors continuously transmit an ultrasonic signal from within the flow stream.
Those signals are reflected off bubbles and particles, and return to the sensor where
frequency shift is measured to derive an average velocity. A differential pressure
transducer in the sensor measures liquid depth to determine the flow area. Flow rate
is then calculated by multiplying the area of the flow stream by its average velocity.
Ceramic crystals transmit acoustic signals (sound pulses) into the flow stream. They
are echoed back after contacting bubbles or particles.
By measuring the difference in frequency between the emitted and returned
signals (known as Doppler shift), the velocities of particles in the flow stream can be accurately determined.
By “range gating” the returned signals, velocity is measured in multiple, distinct cells, called velocity bins. Detailed velocity data in relation to sensor location is then used to calculate a highly-accurate flow profile.
With its sensor mounted above the flow stream, transmitted sound pulses are
reflected off the liquid surface. The elapsed time between transmitted and returned
signals determines liquid level.
Flow rate is then calculated using one of the meter’s built-in flow conversions, or a
user-defined level-to-flow relationship
Especially useful in flow streams affected by harsh weather, debris, or corrosive chemicals, bubbler technology forces compressed air from a submerged tube. The depth of flow is determined by measuring the pressure needed to force the bubbles out of the line. That information is then converted into the flow rate using known parameters.
For sites where wind, steam, foam, or turbulence exist, a probe mounted at the
bottom of the channel measures the pressure of the liquid above to determine
flow stream depth. The level reading is then converted to flow rate using known
The LaserFlow sensor remotely measures flow in open channels with non-contact Laser Doppler Velocity technology and non-contact ultrasonic level technology. The sensor uses advanced technology to measure velocity with a laser beam at single or multiple points below the surface of the water. A non-contacting ultrasonic transmitter measures the liquid head height to determine the wetted area. Multiplying the wetted area by the average velocity yields the flow rate. Flow during surcharge conditions can be measured with an optional, integrally-mounted continuous-wave Doppler area velocity sensor.