Three-dimensional observation of streamer growth and decay processes in cyclohexane

Presents an experimental study of streamer growth and decay processes in cyclohexane. The optical system used in this study basically puts together two sets of the same shadowgraph system. These shadowgraphic images from two different directions were combined through a beam splitter and focused on an image converter camera (ICC) photocathode. These images were reconstructed into the three-dimensional (3-D) images of each frame using an image scanner and a personal computer. Using this system, the growth and decay processes of the streamer were investigated. The volume changes of the streamer were measured by this 3-D observation. A negative hemispherical streamer broke up into small bubbles at its decaying stage. Then these bubbles repeated expansion and contraction. The inner pressure was calculated on this bubble oscillation. From these results, the energy necessary for streamer generation was also calculated.