| 摘要 |
PURPOSE:To easily and accurately detect the boundary surface between two liquid layers in a tank regardless of the kind of liquid including a water medium by shifting an incidence probe and a detecting probe in a position while synchronizing them with each other in the up-down direction. CONSTITUTION:When a suspension of mixed water and oil is settled as it is to separate them, a mixture layer III is present between an oil layer I which is small in specific gravity and a water layer II which is large in specific gravity and sinks downward. An ultrasonic wave pulse is made incident into the liquid in this state through the probe 2 and ultrasonic waves which are transmitted through the oil layer I, mixture layer III, and water layer II and received by a receiver 5 through the detecting probe 3 have waveforms shown by A, B, and C. Namely, the wave which is transmitted through the oil layer I is longer in propagation time than the wave transmitted through the water layer II (T1>T2) and the wave transmitted through the mixture layer III has a composite waveform corresponding to the ratio of the constituent components and two peaks. Therefore, when the waveforms are observed at three vertically adjacent points on the outer periphery of the tank, the presence of the boundary surface can be recognized at the position B of the probe 3. |
