Sonoluminescence as the PeTa Radiation

Abstract

In this paper, a model of cavitational luminescence (CL) and sonoluminescence (SL) is developed. The basis of the model is the PeTa (Perel'manTatartchenko) effect-a characteristic radiation under first-order phase transitions. The main role is given to the liquid, which is where the cavitation occurs. The evaporation of the liquid and subsequent vapor condensation inside the bubble are responsible for the CL and SL. Apparently, the dissolved gases and other impurities in the liquid are responsible for peaks that appear at the background of the main spectrum. They most likely are excited by a shock wave occurred during cavitation. The model explains the main experimental data. Thus, no mystery, no plasma, no Hollywood.

Sonoluminescence as the PeTa Radiation, Part Two

“…This point is the equilibrium one. The condition of equilibrium of forces acting on the wall of the bubble must be fulfilled at this point with respect to Equation (1), which is similar to Equation (6) from paper [2]. The only difference is the absence of a driving mechanical force P D .…”

“…In CL/SL, change in an external pressure is the driving force of the processes. In paper [2], we took into account the change in the pressure, but neglected a possible change in temperature. As a result, we used an isothermal version of the PeTa model sa- In LIBL, the driving force of the process is the temperature change, so we use the isobaric version of the PeTa model, taking into account the temperature change, but neglecting a small change in pressure.…”

“…The external pressure remains constant or even increases due to increased Laplace pressure. Thus, to preserve the mechanical balance of forces acting on the wall of the bubble, gas and vapour in- Let us consider the thermodynamic state of gas and vapour inside the bubble in the process of reducing its size on the basis of the analysis carried out in paper [2].…”

“…[2], it follows that to keep the water vapour in equilibrium inside the bubble, the rate of change of the radius should not exceed 3 m•s −1 . This value was obtained for a reasonable but arbitrary accommodation coefficient α = 0.2.…”

“…This value was obtained for a reasonable but arbitrary accommodation coefficient α = 0.2. The more precise analysis makes it clear that we do not need to choose an arbitrary value for α, but it can be calculated from experiments described in paper [2]. It gives α = 0.1; thus, to maintain the equilibrium vapour pressure, the rate of change of the radius should not exceed 0. , which is 20 times higher than the maximal determined rate.…”