The Relationship Between Breach Development and the Depressurization Transient During Axial Rupture of a Gas-Pressurized Steel Pipe

Theoretical models are developed to predict the depressurization generated by a propagating axial rupture in a gas-pressurized steel pipe. The pressure transient is composed of a relatively slow depressurization within the rarefaction wave which propagates through the undisturbed gas ahead of the developing breach and a rapid depressurization within the breach zone. The models combine a simplified one-dimensional treatment of the gas flow local to the breach with experimental breach area growth data. An instantaneous steady flow through the developing breach is assumed to determine the boundary condition for the rarefaction wave. The breach zone depressurization is assumed to be dominated by the transverse wave action initiated by the arrival of the breach at the observation point. In both cases the predicted transients are in good agreement with experimental pressure histories.