Detonation velocities, description

Refs 1) A. Solem et al, NAVORD 4006 (1955) (Description of plate push test) (Conf) (Not used) 2) Cook (1958), 29 (Pin method for determination of detonation velocity) 3) J.W. Kury et al, 3rdONRSympDeton (I960), Vol 3, p 80 (Description of flat plate test and cylinder test) (Conf) (Not used) 4) M.L. Wilkins, Univ of Calif, Lawrence Radiation Lab, Livermore,... 

About 1943, a simplified method for ealen of deton velocities of solid organic expls was developed at the Explosives Research.Laboratory (ERL), Bruceton, Pennsylvania. As there was no report issued at that time but just an unpublished letter of E.M. Boggs F.J. Martin addressed to Brinkley, a brief description of the method was given by him in Ref 39, p 87 In the ERL method, the general equation of state (See our eq 23), with a single covolume constant per unit mass of gaseous expln product, was used and the decompn scheme which leads to quantitative formation of water,... 

Detonation Velocity can be detd by Dautriche or Chronograph Methods described in Vol 3 of Encycl, pp C311 to C318. Mettegang- and Dautriche Methods have been used at the BurMines and their description is given in Bull 346 (Ref 5, pp60-66)... 

Queen Gray Recorder. An app for measuring the detonation velocity of expls, identical in principle to the Mettegang recorder (see in Vol 8, M122-L). A model was installed and used at PicArsn see the ref for its description Ref I.A. Luke, ArmyOrdn 7. 368 (1926)... 

A general description of Detonation Fuses is given in Vol 3 of Encycl, C529-R to C531-L. Spanish Rapid Fuse consists of a PA (or other brisant HE) core enclosed in a tube of 3.5mm diam made of Sn-Pb alloy. Its deton velocity is from 3 to 7km/sec (Ref 9, pp 62—63 and Ref 13, pp 100 410)... 

Fugacity Determinations of the Products of Detonation were determined by M.A. Cook for PETN, RDX, LNG, Tetryl and 60% Straight Dynamite, by employing the equation of state derived from die hydrodynamic theory and observed velocities of detonation. The so-called reiteration method was developed for solving simultaneously as many equilibria as is necessary to define completely the composition of the products of detonation. Detailed description, together with 14 references is given-in the original article ... 

The first and common description of the explosive performance is the detonation velocity D (measured at a desirably high charge density). This is not sufficient as resulted by our own research on light-element explosives (ANQ, TAGN), which exhibited besides attractive D values only low ballistic performance not predicted by model calculations. So as a second base is applied the Gurney energy JIEq. For a more profound analysis we recommend the brisance of an explosive which can be quantified by the depth (or the volume) of the denting from a detonation on a steel plate, the Plate Dent Test. 

To calculate the resolved reaction zone and the stability of detonations, we wish to use a piston that is as close to the steady-state piston as possible, so that the deviations from the steady-state will be as small as the mesh used will permit. To accomplish this for any desired detonation velocity, the piston velocity was initially set equal to the particle velocity of the undecomposed condensed explosive that corresponds to the detonation (shock) velocity. The piston compresses and heats the explosive next to it, and a certain amount of reaction occurs. The intersection of the Rayleigh line, as shown in Figure 1.2 with the corresponding Hugoniot is used to determine the proper piston velocity for the next time step. The piston velocity computed in this manner approximates the steady-state piston. A detailed description of the method used to compute the steady-state piston is presented in Appendix A. 

In the 1950s, the more descriptive schlieren records of the interactions between pressure waves and deflagration fronts were obtained [16-18], and Oppenheim [9] introduced the hypothesis of the "explosion in the explosion" (of the detonating mixture) occurring in the regime of accelerating flame to explain the sudden change in the velocity of the combustion wave observed in the experiments. 

For more detailed description of particle-velocity measurements, see "Detonation, Particle Velocity in and Its Determination Andreev Belyaev (Ref 44, pp 247-49) describe a method of experimental determination of pressure of detonation, using the arrangement shown in Fig B, Here 1 is charge of an explosive enclosed in a metallic container, and 2 is a metallic (usually aluminum) plate, 1-2mm thick, firmly inserted as a cover at the end of cartridge opposite detonator, 3. On initiation of charge, a shock wave will spread to plate 2 and, when the wave reaches the outer surface of the plate, it will start to move with initial velocity VH (here H is nachaT-naya, which means initial). After determining this velocity experimentally, the... 

Besides description of three approx detonation theories, Cook discussed the relationships between velocities and diameters for several HE s and plotted them on curves shown on pp 47, 48, 49, 50, 129, 130, 131 132... 

C. Fauquignon et al, 4thONRSymp Deton (1965), p 39 (Listed as "Water or plexiglas induced shock wave velocity , without giving its description)... 

Free Surface Velocity (pp 111-16) [See our description under Detonation (and Explosion), Pressures of and Their Measurements, p487] and Billard Ball Mechanism of Vf (t),... 

The question considered is a description of the conditions which must be met by a localized initiator if a spherical detonation wave is to be formed. The first problem is a determination of the possibility of the existence of such a wave. Taylor analyzed the dynamics of spherical deton from a point, assuming a wave of zero-reaction zone thickness at which the Chapman-Jouguet condition applies. He inquired into the hydrodynamic conditions which permit the existence of a flow for which u2 +c2 = U at a sphere which expands with radial velocity U (Here U = vel of wave with respect to observer u2 = material velocity in X direction and c -= sound vel subscript 2 signifies state where fraction of reaction completed e = 1). Taylor demonstrated theoretically the existence of a spherical deton wave with constant U and pressure p2equal to the values for the plane wave, but with radial distribution of material velocity and pressure behind the wave different from plane wave... 

Initiation by Precursor is a phenomenon encountered in low velocity detonations, LVD, in liquid explosives. It depends primarily on cavitation of the liquid by the shock traveling in the container ahead of the shock in the liquid. For a description of this effect, see Low Velocity Detonation in this Vol... 

Dautriche, M thode de (pour mesurer la vitesse de ddtonation)(Dautriche s Method for Measurement of Velocity of Detonation). See Ref 24, p E140-R which includes 8 refs. Detailed description is given in Ref 23, pp C311-R (with Fig) and p C312-L... 

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