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Detonation Velocity and Pressure

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 reaction zone of the detonation wave of an explosive is too thin to identify its detailed structure.C - ] Therefore, the detonation processes of explosives are characterized through the details of gas-phase detonation phenomena. [Pg.257]

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 [Pg.257]

The logarithmic form of Eq. (1.14) gives the specific heat ratio under isentropic change as [Pg.257]

Since pj is much larger than pi in the case of a detonation wave, Eq. (9.3) becomes P] = piUif /(y + 1) (9.4) [Pg.258]

The characteristic values at the Chapman-Jouguet point are also obtained from Eqs. (9.2) and (9.4) asW [Pg.258]

The specific heat ratio, y, expressed by Eq. (1.28), is determined to be 2.85 for high explosives by statistical detonation experiments. Thus, Eqs. (9.4)-(9.6) become ] [Pg.258]

As discussed in Section 3.2.3 of Chapter 3, the derivative of the Hugoniot curve is equal to the derivative of the isentropic curve at point J. Then, Eq. (3.13) becomes [Pg.199]

The pressure pj at the Chapman-Jouguet (CJ) point is obtained using Eqs. (3.12) and (8.2) as12 [Pg.199]


Hybrid compounds containing heterocyclic nitramine and em-dinitro functionality represent a class of high performance energetic materials. Such compounds frequently exhibit higher heats of formation, crystal density, detonation velocity and pressure, and better oxygen balance compared to analogous aromatic compounds. [Pg.276]

Though the theoretical detonation velocity and pressure at the CJ point are expressed by very simplified expressions, the computed results obtained by means of Eq. (9.7) are confirmed by measured data for RDX- and TNT-based explosives, as shown in Table 9.110 (Cp-B indicates Composition B , with the two columns relating to different particle sizes). [Pg.258]

Table 9.1 Density, detonation velocity, and pressure at the CJ point. Table 9.1 Density, detonation velocity, and pressure at the CJ point.
In assessing the potential value of a proposed energetic compound, important measures of performance are detonation velocity and pressure for explosives and specific impulse for propellants. One of the key factors in determining these properties is the energy that is produced in the decomposition or combustion process [1-4]. This can normally be estimated if the compound s heat of formation, AHf, is known. (There are also indications that the energy of decomposition is related to sensitivity toward initiation of detonation [5,6].) Thus a reliable value for AHf is essential to the evaluation of a compound. If the latter has not yet been synthesized, then its heat of formation must necessarily be obtained by a computational procedure. This may be true as well if only a very small amount has been prepared, or if the laboratory determination presents difficulties [7]. [Pg.247]

Chapman-Jouget detonation velocities and pressures, which for a large number of explosives lie within the measurment accuracy of practically obtained values. [Pg.175]

DEMOLITIONS - Very limited in this field due to the low detonation velocity and pressure. Could find specialized uses ... [Pg.42]

The explosive shown below in Figure 3.13 is trinitrochlorobenzene, also called picryl chloride. It is made by direct nitration in the classical sense, by the mixture of nitric and sulfuric acids. The last nitration step is very difficult. It requires maximum acid concentrations and has a relatively low yield. This explosive, therefore, is rather expensive. It is as insensitive as TNT and has a somewhat higher output in terms of both detonation velocity and pressure. The dinitro form is more important because it is used as the starting material in the sjmthesis of several other explosives, as was shown previously. [Pg.35]

One of the crystal forms of NQ (Figure 3.31) is fiber- or featherlike this enables the crystals to mechanically interlock with large void spaces left between them. This property enables NQ to maintain fairly decent mechanical properties (it does not flake or fall apart) at low pressing densities. The ability to maintain uniform low density makes NQ a useful laboratory explosive where some experiments require controllable low detonation velocity and pressure. NQ is made by dehydration of guanidine nitrate, which in turn was made by the reaction of ammonium nitrate with dicyanodiamide. NQ is also used as a major ingredient in triple base gun propellants. [Pg.45]

We saw how the initial density of the explosive affects both the detonation velocity and pressure. [Pg.274]

Section I deals with the chemistry of explosives. It starts with definitions and nomenclature of organic chemicals, based on molecular structure, which is included to bring nonchemists up to speed on being able recognize and describe pure explosive compounds and mixtures and not to be intimidated by chemists jargon. It then describes the many forms in which these explosive chemicals are used. Using molecular structure as the common thread, the text then goes into the estimation of the stoichiometry of oxidation reactions, the prediction of explosive detonation velocity and pressure properties, and the quantitative analysis of thermal stability. [Pg.468]

R. Chirat and G. Pittion-Rossillion employ a simplified Weeks-Chan-dler-Andersen (WCA) perturbation theory while F. Ree uses the Man-soori-Canfield-Rasaiah-Stell (MCRS) hardsphere variational theory. Both methods build on the a-Exp-6 potential and yield the theoretical Chapman-Jouget detonation velocities and pressures, which for a large number of explosives lie within the measurment accuracy of practically obtained values. [Pg.120]

Among the most important functional parameters of the azides are the detonation velocity and pressure, and these depend on the material parameters (density, azide content, particle size, etc.) and the confinement (its material, density, dimensions, etc.). Even with the most modem techniques the functional quantities are not easy to measure with reliability and precision. In this section... [Pg.260]

Determine the detonation velocities and pressures for the following flammable gases methane (CH4), hydrogen (H2), ethylene (C2H4), acetylene (C2H2) in air and acetylene with 2.5 mol of oxygen. [Pg.39]

In searching for new explosives one is most concerned with performance (detonation velocity and pressure), thermal properties, and sensitivity. Whether a new candidate explosive is ultimately widely used may well be determined by other factors, such as cost, toxicity, melting point, etc., but the initial research effort is guided by the trinity of performance, thermal stability, and sensitivity. This presents a difficult multifactoral problem in assessing the various molecular properties that contribute to each of these principal selection criteria. For instance, detonation velocity is affected by density, elemental composition, and heat of formation. These factors must be varied together in such a way as to maximize the combined effect on performance. [Pg.605]

Figures 7.8 and 7.9 illustrate the water steam and carbon dioxide effect on H2 + air mixture detonation velocity and pressure. It is seen that the non-combustion... Figures 7.8 and 7.9 illustrate the water steam and carbon dioxide effect on H2 + air mixture detonation velocity and pressure. It is seen that the non-combustion...

See other pages where Detonation Velocity and Pressure is mentioned: [Pg.496]    [Pg.496]    [Pg.76]    [Pg.369]    [Pg.68]    [Pg.260]    [Pg.210]    [Pg.598]    [Pg.257]    [Pg.260]    [Pg.59]    [Pg.24]    [Pg.894]    [Pg.185]    [Pg.62]    [Pg.269]    [Pg.412]    [Pg.199]    [Pg.200]    [Pg.197]    [Pg.895]    [Pg.95]    [Pg.76]    [Pg.369]    [Pg.75]    [Pg.64]   


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