Flexim FLUXUS F401, Руководство по эксплуатации

Страница: 18 / 160

3 General principles
3.2 Measurement arrangements
FLUXUS F401
2020-06-12, UMFLUXUS_F401V2-1EN
18
The average flow velocity of the fluid is calculated as follows:
v = k
Re
· k
a
·
where
3.2 Measurement arrangements
3.2.1 Terms
Sound path
The distance covered by the ultrasonic signal after crossing the pipe once. The number
of the sound paths is:
• odd if the measurement is carried out in diagonal arrangement
• even if the measurement is carried out in reflection arrangement
v – average flow velocity of the fluid
k
Re
– fluid mechanics calibration factor
k
a
– acoustic calibration factor
Δt
p
– time difference between 2 consecutive pulses
Δt – transit time difference of ultrasonic signals S
1
and S
2
(Δt = t
2
- t
1
)
Diagonal arrangement Reflection arrangement
The transducers are mounted on opposite
sides of the pipe.
The transducers are mounted on the same
side of the pipe.
 t
2  t
p

----------------