Dissipative effect in liquid under exposure to low-frequency sound vibrations

Abstract

The article describes the formation of dissipative structures in a liquid in a metal bowl when exposed to lowfrequency sound vibrations. The fluctuating volumes in a thick layer of liquid, that is, clusters of molecules, which make an oscillatory motion and with a loss of stability occupying a new position in the liquid, are investigated. An external synchronous effect on a group of molecules can lead to increasing oscillations and loss of stability not only inside the liquid, but these groups of molecules can leave the liquid through the free surface.Friction on the outer surface of a bowl made of a conductive bronze-containing alloy, which initiates the occurrence of sound vibrations, gives rise to the appearance of new structures in the fluid inside the bowl. The thickness of the liquid layer is about 50 mm. The coordinated addition of energy to the oscillating microvolumes of water allows them to release their potential energy and turn it into kinetic. Water droplets ejected vertically indicate the existence of intense vertical movement of individual volumes of fluid which create new structures and cells, like Benard cells, resulting from heating and vertical convection, but smaller sizes. The observed phenomenon is similar to “cold boiling”. Here, probably, the potential energy of the compressed water particles is released under the influence of external sound vibrations. Sound analysis was performed using an audio editor for several experiments of various lengths.In this work, the dissipative effect in a thick layer of liquid when exposed to low-frequency sound vibrations and the appearance of structures identical to Benard cells in limited volumes of water (and not in a thin layer) is first investigated. It should be assumed that the effect of sound vibrations can lead to blood turbulization and a change in the physical state of living organisms, which in terms of physical effect can be similar to the state of blood boiling with a rapid rise from the depth of the sea. The phenomenon can be used for the intensification of heat and mass transfer in heat exchange installations.