On the possibility of excitation of standing longitudinal wave in the cylindrical restricted capillary filled with the fluid

The work deals with the problem of fluid flat eigentone production possibility in the restricted cylindrical capillary filled with a fluid. In case when cylinder walls are not absolutely rigid, production of standing flat longitudinal waves is impossible. With cylinder wall density increase approach to a piston standing wave produces an eigentone corresponding to the first natural frequency of a zero radial mode. Examples of calculations of certain capillaries are given. The results of the work may be used in cases of ultrasound application to the problems of particle coagulation.