Effects of wire size on electrical and shock-wave characteristics in underwater electrical explosions of aluminum wires

Abstract

Initial wire resistance is an important parameter in an underwater electrical wire explosion because it directly affects the discharge characteristics of the circuit and indirectly affects the explosion and shock-wave generation. This paper presents a study on how the initial resistance affects electrical and shock-wave characteristics of underwater electrical explosions of aluminum wires with an initial energy storage of ∼53.5 kJ under the optimal mode. Load voltage, circuit current, and shock-wave pressure were recorded and analyzed. The experimental results show that the average of the discharge channel resistance and the total energy deposition all increase with the initial resistance. In addition, there is no simple functional relationship between the energy deposition during the phase transition process and the initial resistance, while the energy deposition during the plasma growth process increases with the initial resistance. As for shock waves at ∼33 cm, it is observed that when the initial resistance increases from 674.82 to 1581.60 μΩ, the peak pressure, energy density, and impulse increase from 12.65 MPa, 2.67 kJ/m2, and 964.51 Pa s to 42.37 MPa, 18.21 kJ/m2, and 1940.42 Pa s, respectively. In other words, for the optimal mode, an underwater electrical explosion with thinner and longer wire is more conducive to generating strong shock waves in the far-field regime. These results should help select loads for underwater electrical wire explosions in engineering applications.