Basic Principles of Vapor Cloud Explosions

Historically, this phenomenon was referred to as unconfined vapor cloud explosion, but, in general, the term unconfined is a misnomer. It is more accurate to call this type of explosion simply a vapor cloud explosion.  

This chapter is organized as follows. First, an overview of experimental research is presented. Experimental research has focused on identifying deflagration-enhancing mechanisms in vapor cloud explosions and on uncovering the conditions for a direct initiation of a vapor cloud detonation. 

Theoretical research is then discussed. Most theoretical research has concentrated on blast generation as a function of flame speed. Models of flame-acceleration processes and subsequent pressure generation (CFD-codes) are described as well, but in less detail. 

Finally, several blast-prediction methods are described and discussed. These methods are demonstrated in Chapter 7 with sample problems. 

FIgura 4.1. Overpressure as a function of flame speed for three geometries. The relationships are based on calculations by use of a self-similar solution (Kuhl et al. 1973). 

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