4 Basics – flow measurement
PIOX S72*
4.3 Acoustic penetration
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UMPIOX_S72xV1-9EN, 2022-05-15
4.2.2
Examples
4.3
Acoustic penetration
The pipe has to be acoustically penetrable at the measuring point. The acoustic penetration is given when pipe and fluid
do not attenuate the sound signal so strongly that it is completely absorbed before reaching the second transducer.
The attenuation caused by the pipe and the fluid depends on:
• kinematic viscosity of the fluid
• proportion of gas bubbles and solid particles in the fluid
• deposits on the inner pipe wall
• pipe material
The following requirements have to be met at the measuring point:
• pipe always completely filled
• no deposits of solid particles in the pipe
• no formation of gas bubbles
diagonal arrangement with 1 beam
reflection arrangement with 1 beam
1 transducer pair
1 sound path
1 beam
1 plane
1 transducer pair
2 sound paths
1 beam
1 plane
diagonal arrangement with 2 beams
reflection arrangement with 2 beams and 2 planes
2 transducer pairs
2 sound paths
2 beams
1 plane
2 transducer pairs
4 sound paths
2 beams
2 planes
Notice!
Even bubble-free fluids can form gas bubbles when the fluid expands, e.g., before pumps and after great cross-
section extensions.
X arrangement
displaced X arrangement
