The Numerical Solution of the Rayleigh-Plisset Equation for Spark Cavitation and Calculation of the Maximum Temperature and Pressure in a Cavity
We study the processes typical for liquids under the influence of powerful impulses of electric current. The maximum temperature and pressure arising in cavitation bubbles at such processes are calculated. To this aim, the main equation of cavitation (Rayleigh - Plisset's equation) is solved numerically. The maximum amplitudes of fluctuations of temperature and pressure in a cavity are calculated during a collapse. The analysis of the process shows the existence of the extreme value of pressure above which the cavitation is not observed. Before the limiting pressure being achieved, the cavity increases several times, collapses and comes back to the initial radius, oscillating near it. The increasing of the maximum value of the bubble radius yields, therefore, the increasing of the extreme values of temperature and pressure in a bubble at a collapse. It is established that the maximum amplitude of a bubble during spark cavitation can reach values of the order 200. This fact gives the evidence of large local pressure and temperature in the cavity at the time of a collapse. These temperature and pressure have been calculated in this work. The main conclusion is made that in a liquid metal's phase the intensive cavitation, with local increasing temperature and pressure in a cavity, is possible. Therefore, the process in question can initiate reactions of nuclear fusion in a liquid metal's phase.