Generation of Two Successive Shock Waves Focused to a Common Focal Point

Generator of two successive shock waves focused to a common focal point has been developed. Cylindrical pressure waves created by multichannel electrical discharges on two cylindrical composite anodes are focused by a metallic parabolic reflector and near the focus they are transformed to strong shock waves. The anodes are energized from separate power supplies and time delay between the discharges can be varied. Schlieren photos of the focal region demonstrated that interaction of the two waves results in creation of a large number of secondary short wavelength shocks. Strong attenuation of the second wave has bee shown by measurements of the shock waveforms at the focus. Localized injury of rabbit´s liver induced by the shock waves has been demonstrated by the method of magnetic resonance imaging. Histological analysis of the liver samples taken from the injured region revealed that the boundary between the injured and health tissues is very sharp.