Abstract
A study is described of cylindrical blast-waves generated in atmospheric air by exploding 14 em-length copper wires of various diameters using a high-voltage capacitor discharge. Schlieren photographs taken with an imageconverter camera show the blast-waves to be consistently axially and radially symmetric with respect to each wire. Wires of diameter 24 swg (0.56 mm) allow the maximum energy transfer from the discharge system, enabling blast-wave velocities of up to 4.5 km S-1 (Mach 13.0) to be achieved with a 30 kV discharge voltage. The measured Mach numbers are used to calculate the peak pressures of blast-waves reflected at a cylindrical surface from shock-wave theory applied to “real” air. These pressures, of up to nearly 2000 atmospheres (200 MPa), are found to be in close agreement with those obtained with a piezo-electric pressure-bar gauge.