The report deals with a task of the acoustic channel. The two main tasks are concerned: to eliminate the influence of the rest recesses for the fluid flow in the pipe and to increase the refraction coefficient of ultrasonic waves. For this the recesses fill up the liquids or jelly which the acoustic impedance change from 0,8*106 kg*m-2s-2 to 5,0*106 kgm-2s-1.
L., et al. (Sat,) studied this question.