| 摘要 |
The ultrasonic flow meter, especially for the measurement of water flows, has a bell-shaped ultrasonic field (6) formed by the ultrasonic signals. The gap between the converters (4,5) is selected as required. The measurement stretch (1) is structured as a non-waveguide, to eliminate reflections or at least mostly, as a pipe (2) with a sound-absorbent cladding (3) of soft rubber or a plastics. The ultrasonic field is generated from a permeable and flat active converter surface (7), and can be in combination with a mirror. The measurement pipe or the cladding has a limit layer (9) and an intermediate layer (10), of water, with different impedances. |
