Multi-dimensional evolution of explosive product gas cloud Part I: Evolution in confined two-dimensional and three-dimensional geometries

The evolution of an explosively-driven gas cloud was studied at different scales, geometries, and confinements. The tests used exploding bridgewires and small PETN charges as the explosion sources and measured the shock wave and gas production. These experiments were imaged with high-speed schlieren imaging to visualize the produced gas cloud and the evolution of the surface motion. The explosive events were confined between two acrylic sheets with a varied confinement thickness. Image processing is used to track the gas cloud and to characterize the complexity of the surface in terms of a fractal dimension. Turbulence quantities are estimated from the refractive images and show variations as a function of confinement thickness.