Citation

Birk AM. Fire Safety J. 1989; 15(4): 277-296.

Copyright

(Copyright © 1989, Elsevier Publishing)

DOI

unavailable

PMID

unavailable

Abstract

A computer model has been developed which is capable of simulating the effects of torch fire impingement on a long cylindrical tank filled partially with liquid and partially with vapour. The model was developed to study the effects of fire impingement on rail and highway tankers carrying hazardous commodities.The model is capable of predicting the transient thermal and structural response of the tank when exposed to the torch fire impingement, including tank pressure, wall and lading temperatures, relief valve flow rates, liquid level and wall stresses and strength.Simulation results for uninsulated tanks show that severe torch fire impingement can result in a tank thermal rupture within a few minutes after torch application, if the torch is applied where the tank wall inner surface is in contact with vapour. The simulations also show that as long as liquid wets the wall in the area of the torch application, and as long as the fluid critical heat flux is not exceeded, thermal rupture is unlikely. However, when the liquid level drops below the area of torch application, as may be the case if the relief valve is operating, the tank is likely to fail within a few minutes if the torch impingement continues.Validation results are presented for the case of an empty full-scale uninsulated tank exposed to a torch fire, and an uninsulated full-scale tank filled partially with propane exposed to an engulfing fire. Simulation results are presented for uninsulated tank-cars filled partially with propane exposed to torch fires applied at different locations around the circumference of the tank. Comparisons are made between the cases involving torch fires and the validation case involving the engulfing fire.