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Basics of Fluidic Oscillation?

Fully electronic, there are no moving parts

Improved reliability, less maintenance

Technology ideally suited for Commercial & Light

Industrial Applications: Rotary Alternative

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Fluidic Oscillation

Inlet

Flow

Tranquilizer

Jet Formation

Nozzle

Oscillation

Chamber(1) (3)

(2)

l Described in 3 elements

Flow Tranquilizer

Jet Formation Nozzle

Oscillation Chamber

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Oscillation Chamber

l An obstacle in the chamber is used

to control the fluid feedback paths.

l As the jet is bent to one side of

the cavity a pressure node isformed. This creates a difference in

pressure either side of the jet and

hence a force is exerted on the jet.

Obstacle

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Oscillation Chamber (cont.)

Obstacle

l The force causes the jet to bend to the

other side of the cavity where the

same effect will be seen.

l This oscillation only depends on the

volume of gas passing through the

nozzle. One oscillation cycle will

represent a characteristic volume of

gas.

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Sensor Technology

Sensors

l Thermo resistive sensors detecting changes in thermaltransfer to the gas.

l Common mode (K, r and Cp) rejected by sensor pair.

R1

R2

V

Sensor Resistance

R = R1 R 2

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Self cleaning

l The dimensionally sensitive zones of

the meter are the areas that see the

highest flows.

Nozzle Exit

Pressure Node Trap

Obstacle Cavity

l Abrasion resistant due to particlesuspension

Obstacle Cavity

Pressure Node Trap

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Key Features of Fluidic Oscillation

Static Metrology: DOES NOT LOCK UP!

No moving parts to replace due to wear

No chance of failure due to aggressive materials in the gas

Solid state meter easier to install (no leveling, wont bind)

Can be over driven with no ill effects

No oil

Quiet

Improved Operation & Maintenance

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Key Features of Fluidic Oscillation

400:1 Dynamic Range

fM 2

+/ .5% 9000 to 300 cfh

+/ 1% 300 to 60 cfh

+/ 2% 60 to 22 cfh

Extended Accuracy

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Rotary Comparison

95

96

97

98

99

100

101

102

0 1500 3000 4500 6000 7500 9000

FLOW RATE (cfh)

ACCURACY%

11M

3M 5M 7M

fM2

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Pressure DropDattus fM2 Pressure Drop in Gas

0

1

2

3

4

5

6

7

8

0 1000 2000 3000 4000 5000 6000 7000 8000 9000 10000

Flow Rate (cu.ft./hour)

PressureLoss(In

chesw.c.)

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Applications

l Fluidic Oscillation is bestsuited for measurement

applications where pressure is available

Upstream of the regulator: capacity of 9000 acfh is

multiplied by pressure factor (3 x greater than 3M rotary)

On pounds delivery: where 5 w.c. drop is not an issue

l Meter potential is limited to design specifications for

pressure drop when measurement occurs atatmospheric conditions

1 drop allows only 3871 acfh capacity

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Functionality

l Market availability as:

Basic Metrology

Electronic Temperature Corrected

Full PTZ Correction

Programmable Fixed Factor Index

Instant Flowrate Display

Communications Capability

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Maintenance Requirements

l Battery Change

10 years: basic

l Accuracy verification

Sonic nozzle, bell or Model 5 transfer prover

Differential pressure test

Standard instrument calibration