To provide an ultrasonic flow velocity distribution meter capable of precisely measuring flow rates and flow volumes of fluid, by appropriately selecting transmission frequencies of ultrasonic waves and incident angles to a pipe.
A clamp-on type Doppler type ultrasonic flow velocity distribution meter is provided, in which the ultrasonic waves enter fluid to be measured inside the pipe from an ultrasonic transducer outside the pipe, and the flow velocity distribution of the fluid is measured by utilizing a change caused by the Doppler effect in frequencies of ultrasonic waves reflected by a reflector in the fluid to be measured. The ultrasonic flow velocity distribution meter is made up so that a wedge with an acoustic transmission capability is interposed between the ultrasonic transducer and a body of the pipe, and the transmission frequencies of the ultrasonic waves are selected while avoiding such frequencies that refraction angles of Lamb waves at the pipe represent critical angles at respective modes, wherein the refraction angles are computed from the incident angle of the ultrasonic waves entering the pipe from the wedge, the acoustic velocity in the wedge, acoustic velocities of transverse wave and longitudinal wave in the pipe, and the board thickness of the pipe.
YAMAMOTO TOSHIHIRO
YAO HIRONOBU
OMURO YOSHINORI
HIRAYAMA NORITOMO
| JP2004061108A | 2004-02-26 | |||
| JPS63304117A | 1988-12-12 | |||
| JP2001304931A | 2001-10-31 |
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