HESCO

2018 Flow FestivalOpen Channel Area Velocity Flow Measurement

Rick DeyKey Account ManagerFlow Meter Products

Teledyne, Isco

Agenda

– Review of basics of Area Velocity flow measurement

– Latest advancements in flow technologies

– When and where to use each– Continuous Wave Doppler– Pulse Doppler– LaserFlow Non-contact

The right product for the application

Isco Flow Measurement Laboratory

Equipment Options

Flexibility Smart Device

2150 Area Velocity Flow Module

Modularity• Up to 4 modules• Set up and

interrogate with 1 connection

• Together today• Separate tomorrow• Redundant system

Battery Powered

Area Velocity Flow Measurement

• Q = A x V– Q is Flow– A is Area

• Level Measurement– Pressure sensor– Ultrasonic

– V is Velocity• Doppler

– Contact – 2150/350 AV Sensor– Non-contact - LaserFlow

Doppler Velocity Measurement

Q = A x V

A = Pressure V = Doppler

Return Spectrum

CWD Velocity Measurement

24" Pipe 0.25% 1780 gpm 8" 4.507 ft/s2150 201K01367 v1.12 Probe 203F00288

0

500

1000

1500

2000

2500

3000

3500

4000

4500

5000

-400 -200 0 200 400 600 800 1000

Frequency

Sig

nal S

treng

th

Continuous Wave Doppler• Advantages

– Works well in depths lower than 24” typically

– 5 – 10% normally– Shotgun pattern

• Good approximation of fluid velocity

– Low power consumption

– Portable– Lower cost

• Disadvantages– Sensor in fluid

• Debris• Rags• Damage• Calibration

– Shotgun pattern• Velocity accuracy

degrades >24”• Better for smaller

pipes

ADFM (Large Pipe)

Acoustic Doppler – Range Gating

Teledyne Isco is proud to present…..

• AccQpulse!

accQPulse Sensor

Velocity Diagnostics

Signal StrengthCorrelation-

Similar to 2150 spectrum

Velocity Bins

Pulse Doppler• Advantages

– Works well in depths above 5” typically

– 2% flow accuracy– Velocity profiling

• Discrete velocity measurement

• Up to 20’ water depth

– Portable or permanent– Non-drifting ultrasonic

level sensor– No calibration

• Disadvantages– Sensor mounted on

the bottom of the channel

• Debris• Rags• Damage

– Needs >5”– Cost– Power– Installation in large

pipe flow

Why use a non-contact flow sensor?

• Safety• Maintenance

Unlock the door to a successful flow monitoring

program

oLaserFlow

Theory of operation

23

LaserFlow Sensor

Return DopplerSignal Light

Flowing Water Stream

V

Below Surface

Ultrasonic Principle of Operation

• Sensor angle prevents moisture accumulation

• Deflector Plate– Dead Band

inside sensor– Zero Dead Band

• Range 0 – 10 feet

0-10 ft

Off-axis reflected energy is weak and misdirected.

On-axis reflected energy is directed back to the sensor. However, the unfocused energy is very weak.

On-axis and focused reflected energy is directed back to the sensor with much intensity.

The frequency shift between the transmitted indicates the flow direction. The magnitude of the shift indicates the velocity.

Theory of Operation

Below the surface

5000 Spectral Velocity Readings

Point of Convergence

In 2 seconds!

Laser Velocity Spectrum

5000 Spectral Samples

Doppler Shift

5000 Spectral Samples

Doppler Shift

Signal

Noise

Doppler Power

Minimum of 1,000

Reading Stored in Memory

Measurement of reading quality

Velocity Diagnostics

Ultrasonic Level Measurement

Laser Velocity Measurement

Multi-point/Multi-depth Velocity Method

Signature Velocity Grid

Sanitary Sewer

Overflow

Pumps turned off created surcharge

Laser was under 15’ of water

Submerged Laser

LaserFlow Fully SubmergedCWD sensor reading velocity

Pressure Sensor reading depth

Typical applications• Collection systems

– Large Pipes (>36”)– Small Pipes (<36”)

Lab Tests

Accuracy

• Current published specification– 4% of Reading

• 3rd Party Tests Results• ITRC (Irrigation Training and Research Facility)

Cal Poly San Luis Obispo, CA– 1.8% Absolute Error

• Alden Research Lab– 2.7% Absolute Error

Acoustic Doppler – Range Gating

LaserFlow vs Pulse Doppler 2%

Multipath Transit Time

LaserFlow vs Transit Time 2%

Installation in front of flume

LaserFlow vs Flume

Low Level/High Velocity

• 1/2”Minimum depth for velocity!

• 15 ft/second maximum velocity!

High Velocity

Slow Velocity

Slow Velocity

Extreme Monitoring

Below 1”

From 6ft/sec to

2ft/sec

2912 Doppler Power

supportreading

Less than 1 GPM

Water level drops as it exits the pipe creating 2 level plains

Application Challenge: Drop Pipe

Remote Ultrasonic Level Sensor

X

Allows LaserFlow to adapt for elevated discharge

Improves performance and flow accuracy

Application Challenge: Rotating Bar Screen Blockage

Pump Station Flow

Storm Water

Laser Doppler• Advantages

– Non-contact flow measurement

– 5,000 readings in 2 seconds

– Multipoint Velocity– Large or small pipes– 4% flow accuracy– Works well in depths

from .5” up to 120” with no decrease in accuracy

– Lowest velocity measurement <.5ft/sec

– Portable or permanent– Non-drifting ultrasonic

level sensor

• Disadvantages– Cost

• > Continuous Wave

• < Pulse Doppler

– Power• DC Applications

– May not work in steam, foam or fog applications

Applications

• Continuous Wave Doppler– I & I Studies– Remote low power applications

• Pulse Doppler– High accuracy billing– Irregular velocity profile

• LaserFlow– High accuracy large or small pipe– Dangerous site conditions– Good hydraulic velocity profile

Summary

• One size doesn’t fit all• Multiple technologies may be required for a

successful monitoring program• Understanding the application is as

important as the technology itself

Teledyne Isco Flow Meters

Questions?