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Old 1st Aug 2008, 06:37
  #845 (permalink)  
Deaf
 
Join Date: Nov 2000
Location: Melbourne,Vic,Australia
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One point that has to be borne in mind with the assorted horror pics etc is the dynamic behavior of metal cracks with gas pressure. A crack normally propagates slowly with fatigue etc. When it gets to a certain length (dependant on material, stress etc) it will propagate at 1/3 speed of sound in metal ie much faster than pressure relief which happens at the speed of sound in gas.

Thus if something like Al skin designed for a few psi pressure suddenly get hit with a slug of gas at high velocity there will be a localised pressure which well may cause the skin to fail and the crack will spread very fast. The airflow does the rest.

Poor explanation I know but modelling this sort of thing is not easy.
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