| 摘要 |
PROBLEM TO BE SOLVED: To provide a method capable of easily detecting a flow state of a liquid object using ultrasonic waves.SOLUTION: An evaluation method of a flow state is a method of emitting ultrasonic waves U toward a liquid detection object D and evaluating the flow state of the liquid object on the basis of reflection signals from the detection object D, and includes the steps of: acquiring a reference waveform Won the basis of a preceding ultrasonic signal; acquiring a measurement waveform Won the basis of a succeeding ultrasonic signal; and evaluating the flow state of the detection object D by a difference between the reference waveform Wand the measurement waveform W. |
