| 摘要 |
PURPOSE:To perform highly accurate measurement by attenuating multiple reflected waves in piping for transferring a fluid, by providing a sonic wave absorber to the surface of the piping while providing an ultrasonic transmitter- receiver on said sonic wave absorber. CONSTITUTION:A sonic wave absorber 14 attenuating multiple reflected waves propagating through piping 1 for transferring a fluid is adhered or formed to the circumferences of the ultrasonic transmitter-receivers 2a, 2b of the piping 1 and the propagation path of reflected sonic waves subjected to multipath reflection in the piping 1. This sonic wave absorber 14 allows the acoustic impedance of the piping and the acoustic impedance matching layer of the sonic wave absorber 14 to coincide in order to absrob multiple reflection waves propagating through the piping 1 and it is necessary to satisfy such a condition that an absorber having good absorptivity is used in the material on and after the acoustic impedance matching layer of the absorber 14. |
