The investigation of the internal acoustic properties of a high voltage arc in water

The internal structure of the arc phase of a high‐voltage discharge in water is characterized by the evolution of water molecules into atomic and ionic components. However, the spatial distribution of these components, in addition to the temperature, vary considerably due to the influx of mass at the bubble boundary. The physical and acoustical properties of this bubble are investigated through the use of a newly developed nonlinear 1‐D fluid code. The model includes dissociation and ionization (through +2 for oxygen), thermal conduction, mass influx due to blackbody radiation at the bubble boundary, and a complete electrical model which includes the calculation of the electrical resistivity of the bubble due to both neutrals and ions. Preliminary results show interesting acoustical phenomena including strong acoustical pulses bouncing inside the bubble. These shock waves reflect off the bubble boundary, forming an inward propagating wave not unlike that of an implosion. The nonlinear inviscid fluid equat...