Flexim FLUXUS H721 - Page 12

3 General principles
3.1 Measurement principle FLUXUS H721
2022-05-15, UMFLUXUS_H721V1-5EN
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Fig. 3.2: Sound path of the signal in the flow direction
c – sound speed
1 – transducer (emitter)
2 – transducer (receiver)
3 – pipe wall
Fig. 3.3: Sound path of the signal against the flow direction
c – sound speed
1 – transducer (emitter)
2 – transducer (receiver)
3 – pipe wall
Fig. 3.4: Transit time difference Δt
1 – signal in the flow direction
2 – signal against the flow direction
c
β
β
α
γ
c
γ
3
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c
α
c
α
reduction of the
sound path
flow direction of the fluid
sound path with flow
sound path without
flow
c
β
flow direction of the fluid
sound path with flow
sound path without
flow
β
α
γ
c
γ
increase of the sound
path
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c
α
c
α
1 2
Δt