Detonations shock-deflagration

Chemical explosives detonate, or deflagrate. Detonating explosives (e.g., TNT or dynamite) rapidly decompose to produce high pressure and a shock front (travels faster than the velocity of sound). Deflagrating explosives (e.g., black and smokeless powders) bum fast, prodr er... 

Pressures of deflagration or detonation shock waves build upon the existing system pressure at the time of the initial blast. When a deflagration starts and then builds to a detonation, the resulting peak pressure can be quite high because the final pressure of the detonation builds on the peak pressure of the deflagration. 

The pressure fronts produced by detonations and deflagrations are markedly different. A detonation produces a shock front, with an abrupt pressure rise, a maximum pressure of greater than 10 atm, and total duration of typically less than 1 ms. The pressure front resulting from a deflagration is characteristically wide (many milliseconds in duration), flat (without an abrupt... 

A physical explosion, for example, a boiler explosion, a pressure vessel failure, or a BLEVE (Boiling Liquid Expanding Vapor Explosion), is not necessarily caused by a chemical reaction. Chemical explosions are characterized as detonations, deflagrations, and thermal explosions. In the case of a detonation or deflagration (e.g., explosive burning), a reaction front is present that proceeds through the material. A detonation proceeds by a shock wave with a velocity exceeding the speed of sound in the unreacted material. A... 

A combustible vapor explodes under a very specific set of conditions. There are two explosive mechanisms that need to be considered when evaluating combustible vapor incidents - detonations or deflagrations. A detonation is a shock reaction where the flames travel at supersonic speeds (i.e., faster than sound). Deflagrations are where the flames are traveling at subsonic speeds. 

Both deflagrations and detonations can produce what a lay observer might describe as an explosion . Nonetheless, a detonation is a special type of explosion with specific physical characteristics. It is initiated by the heat accompanying shock compression it liberates sufficient energy, before any expansion occurs, to sustain the shock wave. The shock wave propagates into the unreacted material at supersonic speed, typically 1500—9000 m/s. We discuss the practical differences between the effects of detonation and deflagration in Chapter 11 on post-blast issues. 

Sessions 1-8 (Shock waves) Sessions 9-H (Development of deton from deflagration) Sessions 12-13 (Stability and sensitivity of expls) Sessions 14-15 (Structure of the deton wave) Session 16 - was not published Sessions 17-19 (Detonation in solid expls) Sessions 20-24 (Thermochemistry and energetics of deton) Session 25 (Measurement of deton pressure and of temp developed on deton) ... 

Through-Bulkhead Initiator TBI. Through-bulkhead initiators are used to transmit a detonation shock wave through a solid steel bulkhead and initiate a deflagration on the opposite side without perforating the bulkhead or otherwise destroying the integrity of the hermetic seal formed by the bulkhead... 

If the assessment of deflagration is difficult, the sample mass and the variable initiator test conducted. In addition, detonation or deflagration can be determined by comparison with energy of shock wave per unit of mass ( A E s /W). 

The book is divided into four parts. The first part (Chapters 1-3) includes brief reviews of the fundamentals of the conversion from chemical energy to aerothermal energy. References listed in each chapter are useful to the reader for better understanding of the physical basis of the energy conversion process energy formation, supersonic flow, shock wave, detonation, and deflagration. The second part (Chapter 4) presents the energetics of chemical compounds used for propellants and explosives, such as heat of formation, heat of explosion, adiabatic flame temperature, and specific impulse. 

Division 1.1 explosives present a mass explosion hazard. They are sensitive to heat and shock and they may either detonate or deflagrate when they explode. Division 1.2 explosives have a projection hazard, but not a mass explosion hazard. Division 1.3 explosives have a Are hazard and a minor blast hazard or a minor projection hazard or both, but not a mass explosion hazard. 

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