Transmission into Liquid Media

Abstract

The efficiency of a radiator operating into liquid media is governed by the degree of approximation of the transmitted wave to a plane wave and the value of the resistive (active) components of its radiation impedance. As we know, the resistive component of the radiation impedance of a circular piston radiator increases with the value of 2πr/λ _l under the condition that 2πr/λ _l < 2 (λ<_l is the wavelength in the liquid, and r is the radius of the radiator). In industrial equipment, this condition is almost always fulfilled. As a rule, when the radiating surface S_r is increased, the matching of the wave system and the transducer with the load, i.e., with the medium, is also improved. On the other hand, an increase in the linear dimensions of the radiating surface upsets the homogeneity of the vibrations, i.e., in addition to the longitudinal modes of the radiator, which form a plane wave with all points of the radiating surface vibrating in phase and with the same amplitude, there also occur complex flexural modes.