Temperature Effect on Detonation Cell Size

The cell size grows with the temperature and reaches its maximum at a fixed pressure (here Pq = 10 kPa), the cell then size decreases as the temperature increases behind the shock wave at fixed density. This is the evidence that the detonation initiation energy, which depends on the ceU size, can be reduced by preheating and pre-compression of an explosive mixture. 

The temperature effect on the transverse detonation cell size is not steady. The variously shaded points correspond to data measured by different authors. The data do not significantly diverge [13]. 

6 Effect of Hydrogenous Mixture Composition on Detonation Cell Size 

The curves a = f(P) with the minimum at slightly increased HAM pressure is explained by a specific pressure effect on the ignition delay described earlier. HAM detonability at increased pressure can be compared with that of some hydrocarbon air mixtures (propane + air, acetylene + air). 

The solid curves show the cell sizes calculated using the ZND detonation model. The minimum cell size corresponds to a stoichiometric H2/air ratio. The cell size increases when 30% volume water steam is added to the mixture. 

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