Explosions Detonation velocity

Computer codes are used for the calculational procedures which provide highly detailed data, eg, the Ruby code (70). Rapid, short-form methods yielding very good first approximations, such as the Kamlet equations, are also available (71—74). Both modeling approaches show good agreement with experimental data obtained ia measures of performance. A comparison of calculated and experimental explosive detonation velocities is shown ia Table 5. 

Explosive Detonation Velocity, m/sec Relative Effectivness TNT = 1.00 Principal Uses... 

Rothstein, L. R., and Petersen, R., Predicting High Explosives Detonation Velocities from Their Composition and Structure, Propellants and Explosives, Vol. 4, No. 4, 1979. 

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. 

The performance potential of an explosive cannot be described by a single parameter. It is determined by the amount of gas liberated per unit weight, the energy evolved in the process (-> Heat of Explosion), and by the propagation rate of the explosive (detonation velocity -> Detonation). If an explosive is to be detonated in a borehole, the... 

L. R. Rothstein and R. Petersen, Predicting High Explosive Detonation Velocities from their Composition and Structures , Propellants and Explosives, 4, 56 — 60 (1979). 

As was covered earlier under deflagration and detona Vion, the detonation velocity of an explosive is the speed at which the detonation wave moves through the explosive. For most of today s (x>nimercial explosives, detonation velocity ranges from about 5,000 fps for ANFO to more than 22,000 fps for high explosives such as cast 50/50 Pentolite. It should also be noted that eveiy explosive compound v/ill have a maxxmuin or ideal detonation velocity, which is referred to as its hydrodynamic velocity. 

Stine, J.R. (1989) "On predicting Properties of Explosives -Detonation Velocity", J. Energetic Materials, in press. 

Table 2.4 shows that one could sometimes reproduce the experimental detonation velocity with BKW calculations that have C-J pressures 100 kbar too high. The explosive detonation velocity was ideal, whereas the C-J pressure was obviously nonideal. 

Explosive Detonation pressure, GPa Bulk specific gravity Detonation velocity, km/s Contains high explosives Heat of detonation kj /g Excavated vol relative to equal wt of TNT... 

Obtaining explosives with the proper energy, form, and detonation velocity is difficult. 

Explosives. The pressure, P, generated by the detonating explosive that propels the prime plate is direcdy proportional to its density, p, and the square of the detonation velocity, (25) ... 

In commercial practice, powdered explosives on an ammonium nitrate basis are used in most cases. Typical detonation velocities are between 1800 and 3500 m/s depending on the metal system to be bonded. The lower detonation velocity range is preferred for many metal systems in order to minimize the quantity of solidified melt associated with the bond-zone waves (12). In addition, subsonic detonation velocity explosives are required for the parallel cladding technique in order to avoid attached shock waves in the coUision region, which preclude formation of a good bond. 

Figure 4.9. Shock pressure versus particle velocity for engineering materials, geological material, and explosive detonation products. Intersection of detonation product curves with nonreactive media predicts shock pressure and particle velocity at an explosive sample interface. (After Jones (1972).)...

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... 

Energy Release in Detonation of Aluminized Explosives. Part I. Effect of Confinement and Charge Diameter on the Detonation Velocity of Minol 2 , ARDE Report 616/44 (July 1944) 30) Anon, Studies of the Preparation,... 

Jr, C.W. Plummer, R.P. Woodburn V. Philip-chuk, Detonation Velocity Determinations and Fragment Velocity Determinations of Varied Explosive Systems and Conditions , National Northern Corp Final Summary Report NNC-F-13, Contract DAI-19-020-50l-ORD-(P>58 (Feb 1958) 12) Anon, EngDesHdbk, Explosives Series, Properties of Explosives of Military Interest , AMCP 706-177 (Jan 1971), 213-225... 

Navez Chronograph. See under Chronographs, Chronoscopes, Chronometers and Other Devices Used in Measuring Velocities of Projectiles in Flight and of Detonation Velocities of Explosives in Vol 3, C305-R... 

Explosive Density g/cc Corrected OB Observed Detonation Velocity (m/sec) Calculated %Error... 

Cook, Detonation Velocities of Ideal Explosives With Inert Additives , UnivUtah, Salt Lake, TechRept No 18, AD 16380 (1953)... 

Brisance. Sand test, 58.5g vs 43.0 for TNT Detonation velocity. 7910m/sec for a cast, unconfined sample 1.0/ diam at d 1.60g/cc Explosion temperature. No cap used 375°... 

Tables 2.1 and 2.2 show that theory enables detonation velocities to be calculated in close agreement with those observed experimentally. This, unfortunately, is not a critical test of the theory as velocities when calculated are rather insensitive to the nature of the equation of state used. A better test would be to calculate the peak pressures, densities and temperatures encountered in detonation, and compare these with experimental results. The major difficulties here are experimental. Attempts to measure temperatures in the detonation zone have not been very successful, but better results have been obtained in the measurement of densities and pressures. Schall introduced density measurement by very short X-ray flash radiography and showed that TNT at an initial density of 1 -50 increased 22% in density in the detonation wave. More recently detonation pressures have been measured by Duff and Houston using a method (introduced by Goranson) in which the pressure is deduced from the velocity imparted to a metal plate placed at the end of the column of explosive. Using this method, for example, Deal obtains the detonation pressures for some military explosives recorded in Table 2.3. More...

Explosive Density (g ml 1) Detonation velocity (ms 1) Streaming velocity (ms1) Detonation pressure (10 Pa)... 

Extension of the hydrodynamic theory to explain the variation of detonation velocity with cartridge diameter takes place in two stages. First, the structure of the reaction zone is studied to allow for the fact that the chemical reaction takes place in a finite time secondly, the effect of lateral losses on these reactions is studied. A simplified case neglecting the effects of heat conduction or diffusion and of viscosity is shown in Fig. 2.5. The Rankine-Hugoniot curves for the unreacted explosive and for the detonation products are shown, together with the Raleigh line. In the reaction zone the explosive is suddenly compressed from its initial state at... 

Explosive m.p.(°C) Density (gmH) Weight strength % Blasting gelatine Maximum detonation velocity (m s- )... 

As the loading density of a powdered solid explosive is reduced the detonation velocity becomes less. This follows from equation (5) of Chapter 2, asp2 is smaller the lower the density. Calculation shows that at the lowest densities the detonation velocity tends towards a limiting lower value, typically about 2000 m s-1. This is also the detonation velocity in a dust explosion of these substances. 

Mixtures with nitrobenzene, 1- or 4-nitrotoluene, 1,3-dinitrobenzene or 1-nitronaphthalene were found to be high explosives of high sensitivity and detonation velocities [1]. Those with nitrobenzene are spark-detonable [2],... 

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