Showing posts with label ISCO. Show all posts
Showing posts with label ISCO. Show all posts

High Velocity Flow Monitoring in a Sanitary Sewer

View of flow inside the pipe
View of flow inside the pipe.
A sanitary sewer within a local municipality had two options for flow monitoring applications. The first application was in front of an overflow bypass gate where standard area velocity flow monitoring technologies were installed and working, but only intermittently. When the gate closed, the water surcharged the pipe until it overflowed into the bypass weir. The AV sensor was no longer able to read the bypass flow because the water at the bottom of the channel was no longer flowing. Another challenge was with the pipe joints creating turbulence.

The alternate flow monitoring location was upstream, in a 42 inch pipe, and on the side of a hill. The level, which is 1-3 inches deep with velocity of 4.5 ft/s, was an additional challenge. Standard in-pipe area velocity sensors are not able to operate in conditions where high velocity effects the depth of the water accelerating over the top of the sensor (Bernoulli Effect) resulting in lower recorded levels.
Chart of the sensors output
Chart of the sensors output (click for larger view)

The solution in this application was LaserFlow. LaserFlow uses a non-contact sensor that utilizes a non-contact ultrasonic level sensor and a laser to read the velocity below the surface. In this application the LaserFlow allowed for accurate readings to be taken even in the most turbulent of flows.

After the initial setup the LaserFlow sensor worked well for several hours. When the level decreased, the laser started to focus on the bottom of the channel due to the steep slope of the pipe. There were two options to correct this issue:
Flow Meter technician in the pipe adjusting the LaserFlow
Flow Meter technician in the pipe
adjusting the LaserFlow.
  • Send a technician back into the confined space to position the LaserFlow sensor parallel with the flow stream. 
  • Change the slope programming setting to match the slope of the pipe without having to enter into the confined space.
It was decided the slope setting would be changed. After determining the slope of the pipe from a 12 foot rise over a 150 foot run =8% slope. After a few program adjustments, the sensor worked flawlessly.


For more information about the Teledyne ISCO LaserFlow, contact Instrument Specialties, Inc. by visiting http://isi.group or by calling 407-324-7800.

Non-Contact Area Velocity Flow Measurement Using Advanced Laser Doppler Technology

laser Doppler flow velocity sensor for open channel flow measurement
Non-contact flow measurement in open channels is
effectively conducted with laser doppler technology
Image courtesy Teledyne ISCO
An effective way to measure liquid flow in open channels employs a combination of non-contact Laser Doppler Velocity technology and non-contact Ultrasonic Level technology. Teledyne ISCO manufactures a variant of their LaserFlow non-contact flow meter that incorporates both velocity and depth sensors into a single compact unit. The sensor uses advanced technology to measure velocity with a laser at single or multiple points below the surface of the water or wastewater stream.

An ultrasonic level sensor provides the depth of the flow, and the system determines a sub-surface point at which to measure velocity. The sensor then focuses the laser at the designated point and measures the frequency shift of the returned light.

This sensor is ideal for a broad range of wastewater monitoring applications and is compatible with readily available flow meters.

With optional continuous wave Doppler Ultrasonic Area Velocity technology flow measurement continues without interruption even while submerged.

A specially designed mounting bracket enables deployment of the sensor in a manner that permits removal from street level, avoiding the risk and expense of confined space entry. A variety of communication options enable programming and data retrieval from a remote location as well. Built-in diagnostic tools simplify installation, maintenance, and advanced communication options reduce site visits.

The sensor provides excellent system versatility across a wide variety of industrial applications to manhole installations, with many configuration options providing the flexibility to measure flow in most open channel applications.

Depending on your application needs, the device can be programmed to take velocity measurements at single or multiple points below the water's surface, producing an accurate mean velocity reading.

In applications where the level measurement point of the built-in ultrasonic and the measurement point of the laser velocity are of different elevations, such as a freefalling outfall or drop manhole, the remote ultrasonic option can be used so that both measurement points reference the same elevation.

During submerged conditions, the optional bottom-mounted area velocity sensor seamlessly takes over the flow rate measurement. The sensor provides ultrasonic Doppler velocity measurement and Differential Pressure level measurement. This option measures flow in the pipe/channel. By measuring velocity over a large area, the ultrasonic Doppler technology provides more accurate flow measurement during submerged conditions.

For redundant flow measurement at critical monitoring sites, a unique flexibility is added by an optional sensor which is mounted at the bottom of the pipe. This sensor provides redundant velocity, level, and flow data from the same site as the device.

Following initial installation and adjustment, the sensor can be installed or removed as needed without manhole entry in most situations, using the optional sensor retrieval arm to grasp the handle. The handle's simple yet effective locking mechanism holds the sensor securely in place, and is easy to engage and release from above ground.

Share your open channel flow measurement challenges with measurement instrumentation experts. Leverage your own knowledge and experience with their product application expertise to develop an effective solution.


Advanced Laser Doppler Technology for Non-Contacting Area Velocity Flow Measurement

Laser Doppler Velocity
Laser Doppler Technology
for Non-Contacting Area
Velocity Flow Measurement
(by Teledyne ISCO)
A new velocity 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 wastewater stream.

An ultrasonic level sensor is used to measure the level and then determines a sub-surface point to measure velocity. The sensor then focuses its laser beam at this point and measures the frequency shift of the returned light.

This sensor is ideal for a broad range of wastewater monitoring applications and is compatible with readily available flow meters.

With optional continuous wave Doppler Ultrasonic Area Velocity technology flow measurement continues without interruption even while submerged.

With a specially designed mounting bracket the sensor can be deployed and removed from street level,  avoiding the risk and expense of confined space entry. A variety of communication options enable programming and data retrieval from a remote location as well. Built-in diagnostic tools simplify installation, maintenance, and advanced communication options reduce site visits.

The sensor provides excellent system versatility across a wide variety of industrial applications to manhole installations, with many configuration options providing the flexibility to measure flow in most open channel applications.

Depending on your application needs, the device can be programmed to take velocity measurements at single or multiple points below the water's surface, producing an accurate mean velocity reading.

In applications where the level measurement point of the built-in ultrasonic and the measurement point of the laser velocity are of different elevations, such as a freefalling outfall or drop manhole, the remote ultrasonic option can be used so that both measurement points reference the same elevation.

During submerged conditions, the optional bottom-mounted area velocity sensor seamlessly takes over the flow rate measurement. The sensor provides ultrasonic Doppler velocity measurement and Differential Pressure level measurement. This option measures flow in the pipe/channel. By measuring velocity over a large area, the ultrasonic Doppler technology provides more accurate flow measurement during submerged conditions.

For redundant flow measurement at critical monitoring sites, a unique flexibility is added by an optional sensor which is mounted at the bottom of the pipe. This sensor provides redundant velocity, level, and flow data from the same site as the device.

Following initial installation and adjustment, the sensor can be installed or removed as needed without manhole entry in most situations, using the optional sensor retrieval arm to grasp the handle.

The handle's simple yet effective locking mechanism holds the sensor securely in place, and is easy to engage and release from above ground.


For more information contact:

Instrument Specialties Inc.
3885 St. Johns Parkway
Sanford, FL 32771
phone 407.324.7800
fax 407.324.1104
e-mail: offices@isisales.com