Abstract
UDC 537.528: 519.6:621.314
DOI https://doi.org/10.52577/eom.2021.57.3.102
The pressure field in discharge chambers of a limited volume with deformable walls very often has a great influence on the efficiency of technological processes of deformation of sheet alloys; therefore, its determination is an urgent task. As a result of an electric discharge in the liquid filling the discharge chamber, in it, a cavity with a higher compressibility is formed than the liquid in the chamber. At the stage of the discharge, this cavity is filled with non-ideal plasma, and after the discharge, with liquid vapor and gases dissolved in it (vapor-gas cavity). Its pulsations form a pressure field in the discharge chamber. The moving boundary of the vapor-gas cavity creates great problems in calculating the pressure field in a liquid, especially after a large number of its pulsations. At present, the role of the vapor-gas cavity in the formation of the pressure field in the discharge chamber with a deformable wall, which is a sheet alloy plate, is insufficiently studied. Its definition is the purpose of this work. The study was carried out on the base of a previously developed mathematical model of an electric discharge in water, which in this work is supplemented with relations that significantly increase the accuracy of calculating the resistance of the discharge channel and the energy released in it. It was determined that the pulsations of the vapor-gas cavity provide pressure fluctuations in it in an antiphase with the average pressure in the liquid. In a discharge chamber with rigid walls, they decay slowly, but the presence of a deformable wall leads to a rapid decay of pressure fluctuations. In the previously developed mathematical model, the change in the optical transparency of the plasma was taken into account, and its significant effect on the pressure in the cavity and the pressure field in the liquid was determined.
Keywords: electric discharge in water, mathematical modeling, discharge channel, vapor-gas cavity, pressure field, discharge chamber.