Blast Effects of BLEVEs and Pressure Vessel Bursts

BLAST EFFECTS OF BLEVEs AND PRESSURE-VESSEL BURSTS 

This section addresses the effects of BLEVE blasts and pressure vessel bursts. Actually, the blast effect of a BLEVE results not only from rapid evaporation (flashing) of liquid, but also from the expansion of vapor in the vessel s vapor (head) space. In many accidents, head-space vapor expansion probably produces most of the blast effects. Rapid expansion of vapor produces a blast identical to that of other pressure vessel ruptures, and so does flashing liquid. Therefore, it is necessary to calculate blast from pressure vessel mpture in order to calculate a BLEVE blast effect. 

This section first presents literature review on pressure vessel bursts and BLEVEs. Evaluation of energy from BLEVE explosions and pressure vessel bursts is emphasized because this value is the most important parameter in determining blast strength. Next, practical methods for estimating blast strength and duration are presented, followed by a discussion of the accuracy of each method. Example calculations are given in Chapter 9. 

The rapid expansion of a vessel s contents after it bursts may produce a blast wave. This expansion causes the first shock wave, which is a strong compression wave 

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