Detonation characteristics

In contrast to the detonation of gaseous materials, the detonation process of explosives composed of energetic solid materials involves phase changes from solid to liquid and to gas, which encompass thermal decomposition and diffusional processes of the oxidizer and fuel components in the gas phase. Thus, the precise details of a detonation process depend on the physicochemical properties of the explosive, such as its chemical structure and the particle sizes of the oxidizer and fuel components. The detonation phenomena are not thermal equilibrium processes and the thickness of the reachon zone of the detonation wave of an explosive is too thin to identify its detailed structure.[i- i Therefore, the detonation processes of explosives are characterized through the details of gas-phase detonation phenomena. 

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W. A. Blaine and co-workers, "Detonation Characteristics of Gun Propellants," preprints of 9th Symposium (International) on Detonation, Portiand, Oreg., Aug. 1989, p. 233. 

R. K. Jackson and co-workers, "Initiation and Detonation Characteristics of TATB," in Proceedings of Symposium on Compatibility of Plastics and Other Materials with Explosives, Propellants, and Pyrotechnics, ADPA, Washington, D.C., 1976. 

VI. Preparation VII. Detonation Characteristics VIII. Thermal Decomposition IX. Combustion DDT (deflagration-to-detonation transition) X. References. The major emphasis will be placed on Sections VII, VIII and IX... 

Detonation characteristics of liquid explosive mixtures with nitrobenzene were studied. 

When mixed with hydrocarbons in approximately stoicheiometric proportions, a sensitive highly explosive mixture is produced which needs careful handling [1,2], The use of such mixtures as rocket propellants has also been investigated [3], Explosion of only 10 g of a mixture with toluene caused 10 deaths and 20 severe injuries [4], The mixture contained excess toluene in error [5], Detonation characteristics of mixtures with benzene, toluene (and nitrobenzene) were studied [6],... 

Zeman, S., "The Relationship between Differential Thermal Analysis Data and the Detonation Characteristics of Polynitroaromatic Compounds," Thermo-chimica Acta, 41 (1980). 

There is also an opportunity to use the concept of controlled in-chamber blending of two fuels exhibiting different detonability characteristics [17]. 

MP 42, 83-144(1960) (9 refs) (Calcn of detonation characteristics for condensed expls) E) J. Berger et al, AnnPhys [13], 5, 1144-76 (I960) CA 55, 10890-91(1961) (Determination of detonation characteristics of solid expls) F) H.H. Licht,Explosivstoffe 15(4), 73-8(1966) CA 65, 13488(1966) (Calculation of Detonation Characteristics by Means of a Differential Decomposition Equation) (See also Detonation Parameters and Detonation Properties)... 

Annales de Physique 5 [133, 51 1144-76 (1960) (Determination of detonation characteristics of solid explosives) 6) C. Fauquignon et al, "Detonation of a Cylindrical Charge. 

Several of the potentially useful LOX compositions with some of their physical and detonation characteristics are listed in Table 2 (taken from Ref 6). Some recent LOX compositions are given in Section 5... 

Unlike the relation between brisance and PCJ, expl strength is not readily related to some detonation characteristic of the explosive. Attempts to relate strength to detonation energy are not wholly successful. Relative strength, based on ballistic mortar tests, correlates rather well with computed nRT, where n T are the computed moles of gas and detonation temp of the explosive, and R is the gas constant. Although n T can differ appreciably with the equation of state used in the computation, it appears that ratios of nRT (at least for similar explosives) do not suffer from this drawback... 

Sensitivity and Hazards ofLP. Some mono-proplnts and some well-mixed biproplnts exhibit detonation characteristics typical of Liquid Explosives (See Sects 4 5 of article on Liquid Explosives in this Vol). However, biproplnts usually do not sustain complete detonation, ie, a rather small portion of the biproplnt undergoes something akin to detonation and the remainder deflagrates (Ref 26). Of course even this partial detonation can be very dangerous and destructive. LP are also subject to another phenomenon which is potentially destructive (at least to the rocket), namely combustion instability (Refs 16 22)... 

The basic equations for describing the detonation characteristics of condensed materials are fundamentally the same as those for gaseous materials described in Sections 3.2 and 3.3. The Rankine-Hugoniot equations used to determine the detonation velocities and pressures of gaseous materials are also used to determine these parameters for explosives. Referring to Section 3.2.3, the derivative of the Hugoniot curve is equal to the derivative of the isentropic curve at point J. Then, Eq. (3.13) becomes... 

Since the pressure generated by a gaseous detonation is of the order of 10 MPa, the equation of state for an ideal gas represented by Eq. (1.5) is considered to be valid for use in the computation of detonation characteristics. However, the pressure... 

Akhimova Stresik (Ref 17) studied the detonation characteristics of Ammonium Perchlorate (AP) mixed with various fuels . They were primarily interested in the failure diameter (critical diameter) of these mixts, but they do report some detonation velocity measurements at the critical diameter of the mixts... 

TNT. A similar relation is reported for brisance by Trauzl test. In dry mixts the expln efficiency decreases with increasing TNT content (as a result of incomplete reaction), and increases in the case of w-filled expls. The author concludes that for dry mixts the stoichiometry ratio of components prevails, while in w-filled samples the brisance effect is greater for mixts rich in TNT] 2) Y. Bernard et al, Detonation Characteristics of Liquid Nitropropane n—Nitric Acid Mixtures , CR, AcadSciParis, Ser A, B293B (20), 1096-99 (1966) (Fr) CA 68,39485 (1967) [The authors report on the deton parameters of the subject mixt. They found that the deton vel ( 6.5km/sec) decreases linearly with increasing initial temp (0 to 29°) and w content. The calcd deton pressure for the reaction (including w) is of the order of 140kilobars]... 

Safety. 1) CM. McCloskey A. Ellis, Effect of Moisture on the Ignition, Burning and Detonation Characteristics of Benzoyl Peroxide , TechPapRegTechConfSocPlastEngClevelandSect 1966, 68-71 (Sept 1966) CA 66, 12613 (1967) [Table 6 reports data obtd by ign of various w-filled samples of the peroxide in an instrumented pipe, 15"xl.2", using nichrome wire... 

Other Properties. THERMAL STABILITY. Several attempts have been made to correlate knock resistance with thermal stability. Petrov (162) attempted to account for the knock characteristics of various gasoline fractions in terms of their cracking products. Rice (177) showed that a parallelism existed between yields of cracking products and knock tendency. Estradgre (60) did not find a direct relation between temperature for initial cracking and detonation characteristics. 

Detonation Characteristics of Selected Commercial Slurry Explosives... 

Thermochemical data on expls are well documented in this Encycl and elsewhere. The heats of combustion and of expln are listed in Vol 4, D380 to D-3 81. The Standard Heats of Formation and the Heats of Detonation of common expls are found in Vol 7, H41 to H43, those of nitroalkanes in Vol 7, H54. The heats of phase change are tabulated in Vol 7, H44, and the thermal conductivities and specific heats in Vol 7, H45 to H46. The Free Energy Functions of the Detonation Products were listed in Vol 8, P388. A discussion of the thermochemical and detonation characteristics of liq expls are tabulated in Vol 7, L26-L to L34-R. Important... 

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