Denis Funk FLEXIM Flexible Industriemesstechnik GmbH

1. Reduce water loss and
prevent hygienic risk in
your drinking water
network!
Non-invasive measurement solutions
Denis Funk

3. Housing
Straps
Transmitter

4. Transducer
Cable
Transmitter

5. ሶ
𝑽 = 𝑨 ⋅ 𝒗A
𝒗𝑨 = 𝑲𝑹𝒆 ⋅ 𝑲𝒂 ⋅
𝜟𝒕
𝟐𝒕𝒇𝒍
ሶ
𝑉
𝑣𝐴
𝐴
𝐾Re
𝐾𝑎
Δ𝑡
𝑡𝑓𝑙
Volume flow
Average flow velocity of the fluid
Pipe cross-section area
Fluid-mechanical corretion factor
Acoustical correction factor
Transit-time difference
Transit-time
Two ultrasonic transducers are mounted
with a defined distance onto the pipe. By
sending sound signals alternating with and
against the flow, a transit time difference
can be measured. This corresponds to the
flow velocity.

6. ▪ Speed of sound in water is
related to the temperature of
the water
▪ FLUXUS devices measure
the speed of sound of the
media the ultrasound is
propagating through
▪ FLUXUS WD series
calculates the water
temperature from the
measured speed of sound

8. 8
Challenging outdoor
conditions:
▪ Submersion
▪ Flooding
▪ Buried installations

9. ▪ No connectors
▪ Fully sealed design
▪ IP68 option available
▪ Robust
▪ Tamper proof mounting
▪ Long-term stable

13. 13
Challenging ambient conditions:
▪ Temperature fluctuations

14. ASME MFC-5.1-2011:
▪ 4. Uncertainty sources and
uncertainty reduction
“…the flow velocity is
calculated from the transit times;
the sound speed and the angle
in the coupling wedge. A
temperature influence from
temperature dependency of the
sound speed, c, may be
compensated for.”
Piezo
sensor
Piezo
sensor
Temperature
sensor
Temperature
sensor

16. Uncertaintiy & Repeatibility
▪ Each set of transducers and transmitter are calibrated
independently.
▪ Factory calibration certificate issued for transmitter and
transducer pair.
Parameter Description Uncertainty Repeatability
Volume flow Measuring system ±0.3 % of reading ±0.005 m/s 0.15 % of reading ±0.005 m/s
Volume flow Measurement at application ±1 % of reading ±0.005 m/s 0.15 % of reading ±0.005 m/s
FLEXIM Aperture Calibration
World‘s unique and most precise calibration method of ultrasonic
clamp-on flow meters.

17. ▪ Every transducer pair manufactured with matched piezo crystals to
maximize measurement performance and low flow resolution

19. Calculating the effects of the
water supply interruption:
▪ Are there other pipes that lead
into the affected area?
▪ Are these pipes sufficient to
supply the affected area?
▪ Or is a bypass required?
▪ Informing of the supply
interruption
19

20. 20
▪ Shutting off the pipe
▪ Cutting the pipe
▪ Welding the flanges
▪ Installing the flow meter

21. Restarting the water supply:
▪ Reopening the pipe
▪ Flushing the pipe
21

22. 22
▪ Determining pipe
parameters
▪ Installing transducers
▪ Connecting the transducers
and parameterizing the
transmitter

23. The total cost of ownership (TCO) is the purchase price of an asset plus the costs of
operation.
▪ Assessing the total cost of
ownership represents taking a
bigger picture look at what the
product is and what its value is
over time.
▪ FLEXIM’s flow meter may have
higher initial costs but in
comparison to conventional flow
meters they have a much more
economical footprint.

24. Flow meter for the water industry
▪ Measurement uncertainty (system): ±0.3% of reading ±0.005 m/s
▪ Measurement uncertainty (at application): ±1% of reading ±0.005 m/s
▪ Repeatability: 0.15% of reading ±0.005 m/s
▪ Temperature measurement accuracy of ±0.2 K
▪ Outstanding low flow resolution down to 0.01 m/s
▪ Permanently drift-free and no zero-calibration needed
▪ IP68 transducers
▪ Permanent maintenance-free coupling pads

25. Simply clamp on your next
flow and temperature
measurement!
Denis Funk
dfunk@flexim.de

27. Disturbance type: 90° bend
Inlet: I ≥ 10D Outlet: I ≥ 5D
Disturbance type: valve
Inlet: I ≥ 40D Outlet: I ≥ 5D
Disturbance type: compressor
Inlet: I ≥ 20D
Disturbance type: Double 90° bend (2 planes)
Inlet: I ≥ 40D Outlet: I ≥ 5D
Disturbance type: Reducer
Inlet: I ≥ 10D Outlet: I ≥ 5D

28. ▪ In the often-limited space of industrial process plants, recommended straight run
requirements can be difficult to find.
▪ Due to restricted pipework, it’s not always possible to carry out optimum installation as
advised, away from valves, bends and other inline components that could cause
excessive and problematic turbulence.
▪ For accurate measurement to be achieved, clamp-on flow meters normally require an
inlet length of at least 10D.
Disturbed flow profile at
the disturbance
Fully developed flow
profile

29. ▪ As part of the development, FLEXIM collaborated with the highly respected PTB (National
Metrology Institute of Germany) on a research project focusing on the exact determination of flow
profiles.
▪ Calibration was used to determine the disturbance corrections implemented in the meter, firstly
under undisturbed conditions, and then under disturbed conditions.
▪ This allowed the disturbance correction to be obtained from the ratio of the two results, and the
procedure was repeated for all types of disturbance that require a correction function to be put in
place.

30. Thanks to FLEXIM’s disturbance correction, good accuracy is achieved even at non-ideal inflow conditions,
reducing the required inlet length from 10D to just 2D. This innovation means that installation is achieved in even
the tightest of spaces, without process interruption.
-12%
-10%
-8%
-6%
-4%
-2%
0%
2%
4%
0 10 20 30 40 50 60
Error
[%]
Distance [D]
Without disturbance
correction
With disturbance
correction

31. The disturbance correction is applicable for all path configurations that compensate cross-flow. These are
reflect path configurations and cross path configurations (X arrangement or displaced X arrangement).
Although the disturbance correction is optimized for 90° bends and double bends (in and out of plane), it
improves the accuracy of other types of disturbances as well.

32. Because FLEXIM’s Flow Disturbance Correction reduces the required inlet
length from 10D to just 2D, accurate measurements are guaranteed, even
with non-ideal installation conditions.
▪ Accurate measurements even with non-ideal installation conditions.
▪ Effects of flow disturbances (for example after bends) are significantly mitigated.
▪ Results in maximum flexibility and cost savings for planners and users.