| 摘要 |
<p>Disclosed is a flow rate measuring device using guided waves such that ultrasonic wave frequencies are optimized, that the amount of energy injected from ultrasonic wave transmission/reception elements is increased, that the flow sensitivity rate is raised, and that as a result, the measurement accuracy is improved. The aforementioned flow rate measuring device is characterized in that the frequency of that peak among a plurality of peaks of group velocities of guide waves which is an isolated peak of group velocities of guide waves, is set to agree with the characteristic frequency of the ultrasonic wave transmission/reception elements, and that the semi-amplitude values of ultrasonic wave power spectra which are excited/received by the ultrasonic wave transmission/reception elements are set to values which do not duplicate other peaks of group velocities.</p> |
