A perturbation analysis of rapid crack propagation in pressurised pipe

摘要

A steady state analysis is given which models rapidcrack propagation in a pressurised pipe as a beam. The interactionof the gas escaping through the crack flares the pipe giving agreatly enhanced energy release rate G. The solution shows aclear maximum in G which is confirmed with numerical results.Experimental decompression times are also predicted by themodel. Perturbations in the crack speed can be deduced from thesteady state solution and these are shown to be harmonic and ingood agreement with observations. It is also suggested that thesespeed oscillations could give rise to crack snaking.