SWACER mechanism

Intense mixing of burned and unbumed components within large, coherent, turbulent, eddy structures of a jet may lead to local conditions that may induce the SWACER mechanism and trigger detonation. 

Depending on the amount of inhibitor used, initiation of detonation could be delayed for as long as 30 to 45 minutes As pointed out by Wilson (Ref 26) such iong delays are quite inconsistent with the so-called SWACER mechanism... 

It was found that the strength of the fuel/air blast thus initiated depends primarily on the effectiveness and rate of free radical source dispersement thruout the vapor cloud. All these observations are not in accord with the claimed universality of the SWACER mechanism. A broad-brush reaction mechanism based on competition of chain branching and chain breaking is presented... 

There are experiments with mixtures in which parameter non-uniformity was created by a jet of hot combustion products [39]. Self-ignition of such a mixture leads to detonation wave generation. The experimental results obtained in free clouds of low-sensitivity air mixtures can also be an example of the SWACER -mechanism causing detonation initiation [40]. 

One DDT mechanism is SWACER ( Shock Wave Amplification by Coherent Energy Release ) based on a stimulated release of the chemical energy which goes synchronous with the shock wave. 

Abnormally rapid explosion development has been reported in the experiments [38] with high-sensitivity mixtures (Ha + CI2, Ha + Oa with Cla additive) irradiated with ultraviolet rays causing an inhomogeneous distribution of free radical concentration. Existence of optimal radiation intensity causing a shock wave of the largest amplitude has been proved. The authors in [38] have proposed an alternative term for the gradient mechanism of shock wave amplification - SWACER (Shock Wave Amplification by Coherent Energy Release). 

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