Underwater spherical shock wave

Summary form only given. The results of experimental and numerical studies of spherical implosion of converging spherical strong shock waves (SSW) generated using underwater electrical explosion of spherical Cu wire arrays are reported. In the experiment, a ~ 4 kJ pulse generator with discharged current amplitude -300 kA, and a rise time of ~ 1 μs was used for wire array explosion. Spherical wire arrays with radii of 10 mm, 12.5 mm, 15 mm and 20 mm were tested. Number of wires was varied in the range 20-40 for different wire diameters in the range 0.1-0.2 mm. A largest shock wave velocity, pressure, water temperature and density in the vicinity of the implosion origin were achieved for the array with radius of 10 mm. The emission from the plasma formed by SSW near the origin of implosion was collected by optical fibers and detected by photomultipliers. The time of the water self-emission appearance together with the data of energy delivered to the wire array were used for determination of the SSW and water parameters in the vicinity of the implosion center using hydrodynamic simulations coupled with SESAME data base for water.