Numerical simulation of energy deposition improvments in exploding wire by using parallel wire

Summary form only given. Electrical wire explosion is an effective method of nano-powder preparation. However the energy deposition process of fine wires under vacuum or low gas pressure circumstances is usually terminated prematurely due to the flashover along the surface of wires; therefore energy deposited into wires can be far less than the amount needed to fully vaporize them, which leads to quality reduction. In this paper, a parallel wire is introduced in order to improve the energy deposition of the concerned wire before flashover takes place. Wire explosion driven by current with dozens of ns rise time and ~1kA amplitude was studied numerically, and results of simulation showed that by using a parallel wire of certain size, the voltage rising rate was suppressed and the flashover was delayed; therefore the energy deposited into the concerned wire was increased. Under specific assumptions, efficiency of this method is mainly determined by the impedance of the parallel wire which is decided by both the size of parallel wire and the current flowing through it. According to numerical results, this impedance drops monotonously with the diameter of the parallel wire increasing and it shows a feature of “fall-rise” with the length increasing. Energy deposited into concerned wire shows an opposite feature of “monotonous rise” and “rise-fall” with the diameter and length of the parallel wire increasing respectively. So it is possible to improve the quality of electrical explosion nano-powder by choosing parallel fine wires of proper size.