Mutual interaction of two shock waves with a different time delay

Abstract

Generator of two successive shock waves focused to a common focal point has been developed. Two cylindrical pressure waves are generated by multichannel electrical discharges on separated electrodes with different diameters. Time delay between the discharges can be varied. Propagation of the waves has been studied by means of Schlieren photography and polyvinylidene fluoride (PVDF) shock gauges. Interaction of the shock waves takes place twice: inside the reflector volume and in the focal region. It was found that the mutual interaction of the waves inside the reflector volume (time delay up to 30 µs) influences propagation of the first wave, while propagation of the second wave is influenced at all time delays measured. Schlieren photos of the local region demonstrated that interaction of the two waves results in creation of a large number of secondary short wavelength shocks.