Detonation burning

In thermobaric weapons, first anaerobic detonation occurs within the microsecond time-frame, followed by a post-detonative combustion which is also anaerobic and occurs in the hundredth of a microsecond time-frame. Only then, the post detonative burning occurs, which lasts several milliseconds and generates strong heat radiation even at small shock-wave pressures (approx. 10 bar)... 

Propellants. Explosives which burn at a steady speed and can be detonated only under extreme conditions. 

High explosives. Those explosives which normally burn without undue violence when ignited in an open space, but which can be detonated by a sufficiently large sudden mechanical or explosive shock. 

Picric acid is used on a large scale as a high explosive, but for this purpose requires a detonator. If a few small crystals of the pure acid are heated on a crucible lid, they first melt, and ultimately burn harmlessly with a smoky flame. Metallic salts of picric acid are much less stable than the free acid,... 

A comparison of the characteristics associated with propellant burning, explosive detonation, and the performance of conventional fuels (see Coal Gas, NATURAL Petroleum) is shown ia Table 1. The most notable difference is the rate at which energy is evolved. The energy Hberated by explosives and propellants depends on the thermochemical properties of the reactants. As a rough rule of thumb, these materials yield about 1000 cm of gas and 4.2 kj (1000 cal) of heat per gram of material. 

Exothermic oxidation—reduction reactions provide the energy released in both propellant burning and explosive detonation. The reactions are either internal oxidation—reductions, as in the decomposition of nitroglycerin and pentaerythritol tetranitrate, or reactions between discrete oxidizers and fuels in heterogeneous mixtures. 

The procedures commonly used to demilitari2e conventional munitions iaclude munitions disassembly, washout or steamout of explosives from projectiles and warheads, iaciaeration of reclaimed explosives, and open burning or detonation. Open burning and detonation of large quantities of... 

The criteria for insensitive explosives subjected to ha2ard tests permit no reaction more violent than burning in slow and fast cook-off tests and fragment and bullet tests, no propagation in sympathetic detonation tests, no detonation when stmck by a shaped charge jet, no sustained burning when hit by a small fragment, and such special tests as may be required by the use of the explosive. 

D. Price, J. E. Wehner, and G. E. Robertson, Transition from Slow Burning to Detonation Kole of Confinement, Pressure Eoading and Shock Sensitivity, TR68-138, Naval Surface Weapons Center (NSWC), White Oaks, Md., 1968. 

Alternatives to Open Burning Open Detonation of Propellants andExplosives, CPIA PubHcation 540, CPIA, Laurel, Md., Mar. 1990. 

Materials that on shor t exposure could cause death or major residual injury 4 Materials that will rapidly or completely vaporize at atmospheric pressure and normal ambient temperature, or that are readily dispersed in air and will burn readily 4 Materials that in themselves are readily capable of detonation or of explosive decomposition or reaction at normal temperatures and pressures... 

Fire Hazards - Flash Point Data not available Flammable Limits in Air (%). Not pertinent Fire Extinguishing Agents Water, dry chemical, carbon dioxide, foam Fire Extinguishing Agents Not to be Used Not pertinent cial Hazards of Combustion Products Vapors are toxic Behavior in Fire Can detonate or explode when heated under confinement Ignition Temperature Data not available Electrical Hazard Not pertinent Burning Rate Not pertinent. 

Chemical explosions are uniform or propagating explosions. An explosion in a vessel tends to be a uniform explosion, while an explosion in a long pipe is a propagating explosion. Explosions are deflagrations or detonations. In a deflagration, the burn is relatively slow, for hydrocarbon air mixtures the deflagration velocity is of the order of 1 m/s. In contrast, a detonation flame shock front is followed closely by a combustion wave that releases energy to sustain the shock wave. A... 

A UL Type 1 deflagration flame arrester must undergo an endurance burn test while a UL Type 11 deflagration flame arrester must be subjected to a continuous flame test. The test conditions for the endurance burn test and the continuous flame test for a deflagration flame arrester are the same as for a detonation flame arrester. 

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