Flexim PIOX S72 Series, Руководство по эксплуатации

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3 General principles – analysis
PIOX S72* 3.1 Measurement principle
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UMPIOX_S72xV1-9EN, 2022-05-15
3 General principles – analysis
3.1 Measurement principle
The ultrasonic transducers are mounted on the pipe which is completely filled with the fluid. The ultrasonic signals are
alternatively emitted and received by the transducers. The physical quantity is determined from the transit time of the
ultrasonic signals.
Transit time measurement
The average of the transit times of the ultrasonic signals in the fluid and the length of the sound paths in the fluid are used
for the calculation of the sound speed. By using the average, the sound speed is independent of the flow velocity of the
fluid. The physical quantities for analysis are determined by the sound speed.
Calculation of the sound speed
c
γ
=
where
The ultrasonic analyzer PIOX S can provide information about composition of mixtures. For this purpose, the sound speed
and the temperature are measured and the physical quantity for analysis is determined by means of the data sets stored
in the transmitter.
For the standard data sets, the physical quantities for analysis from Tab. 3.2 are selectable.
Customized data sets with special physical quantities for analysis can be created in the FLEXIM laboratory.
Fig. 3.1: Path of the ultrasonic signal in the flowing fluid
Fig. 3.2: Average of the transit times in the flowing fluid t
γ
c
γ
– sound speed in the fluid
l
γ
– sound path in the fluid
t
γ
– average of the transit times in the fluid
t
γ
l

t

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