抄録
Meaurement of interface positions between liquid-liquid phases and liquid-gas phases are one of important problems in order to control chemical processes. We have developed ultra-sonic sensing methods for such interfaces in very corrosive chemicals. Two cells made of glass are used to evaluate sonic velocity and to confirm time difference between sonic source and interfaces. Each sound velocity in each phase of stratified layers agrees to that of pure liquid. Because sounds reflected from interfaces make complicated signals, we used a video observation to record sound signal and phenomena in the test cell and succeeded to recognize each reflected sound from each interface.
