Correct Definition of Sound Speed and Its Consequences in the Tasks of Hydrodynamics

Abstract

The paper considers the applied problems of hydrodynamics and based on the new results, published by the author in recent years, shows that main assumptions used in the course of their solution, namely, incompressibility of liquids and potentiality of their movement, are not applicable to liquids in the gravitational field of the Earth.

The Linearity of the Euler Equation as a Result of the Compressibility of a Fluid

“…Contradictions that are present in the theory of surface waves are described in detail in the works [16] and [19]. In this work, through the example of capillary waves we have explicitly investigated the causes of these contradictions and showed how to overcome them.…”

“…This result was obtained under the assumption of the potentiality of motion and incompressibility of a fluid, on which the entire existing theory of gravitational waves is based [2]- [15]. In the work [16] it was shown that the movement of fluid in a gravitational field of the Earth cannot be potential. It was also shown that the condition of incompressibility is inapplicable to liquids, because it leads to the existence of an internal wave [1], the nature of which is completely inexplicable from the point of view of physics.…”

“…It was also shown that the condition of incompressibility is inapplicable to liquids, because it leads to the existence of an internal wave [1], the nature of which is completely inexplicable from the point of view of physics. This conclusion was made on the basis of a lary-gravitational wave, and it becomes purely capillary [16]. The further investigations of gas and hydrodynamics have shown that Euler equation (fluid motion equation) also must be subject to refinement, since for it assumes that the density of a fluid is constant.…”

“…In addition, it will be shown that there is no stability condition for a capillary wave, i.e. it is always stable in the first equation of system (72) in [16] typo, which the interested reader can easily correct.…”

Investigation of Parameters Affecting Underwater Communication Channel

“…Studies in the field of underwater communication began with the experiment of a physicist/engineer Jean-Daniel Colladon and a mathematician Charles-Francois Sturn in 1826. They obtained that the sound was transmitted in the water faster than in the air [2]. With the subsequent studies, this research area has become interesting, with the necessary knowledge base to examine underwater acoustic communication today.…”