Abstract Not all accidental releases of flammable gases and vapors create explosions. Most releases do not find an ignition source, and of those that do ignite, most of them result in deflagrations that generate low or moderate overpressures. Under some circumstances, however, it is possible for deflagration-to-detonation transition (DDT) to occur, and this can be followed by a propagating detonation that quickly consumes the remaining detonable cloud. In a detonable cloud, a detonation creates the worst accident that can happen. Because detonation overpressures are much higher than those in a deflagration and continue through the entire detonable cloud, the damage from a DDT event is more severe. This paper first provides a brief summary of our knowledge to date of the fundamental mechanisms of flame acceleration and DDT. This information is then contrasted to and combined with evidence of detonations (detonation markers) obtained from large-scale tests and actual large vapor cloud explosions (VCEs), including events at Buncefield (UK), Jaipur (India), CAPECO (Puerto Rico), and Port Hudson (US). The major conclusion from this review is that detonations did occur in prior VCEs in at least part of the VCE accidents. Finally, actions are suggested that could be taken to minimize detonation hazards.

中文翻译：

---

蒸气云爆炸中爆轰的机理和发生

摘要 并非所有易燃气体和蒸气的意外释放都会引起爆炸。大多数释放都没有找到点火源，而在那些确实被点燃的释放中，大多数会导致爆燃，从而产生低或中度的超压。然而，在某些情况下，可能会发生爆燃到爆轰转变 (DDT)，随后可能会发生传播爆炸，迅速消耗剩余的可爆云。在可引爆的云中，爆炸会造成可能发生的最严重的事故。由于爆轰超压远高于爆燃，并持续贯穿整个可爆云，因此 DDT 事件造成的损害更为严重。本文首先简要总结了我们迄今为止对火焰加速和 DDT 基本机制的了解。然后将此信息与从大规模试验和实际大型蒸汽云爆炸 (VCE) 获得的爆炸证据（爆炸标记）进行对比并结合，包括在邦斯菲尔德（英国）、斋浦尔（印度）、CAPECO（波多黎各）发生的事件，和哈德逊港（美国）。本次审查的主要结论是，至少在部分 VCE 事故中，之前的 VCE 中确实发生了爆炸。最后，建议了可以采取的行动，以尽量减少爆炸危险。