Spherical Detonation Wave

Taylor (Ref 23) stated that ignition of TNT chge at some point inside the expl, results in a very rapid drop in pressure velocity behind the deton front. A fixed proportion of the whole vol of burnt gas is at rest and the radial rat e of change of the variables velocity, pressure density become finite at the deton front. The fact that the velocity drops to ze ro at some point between the deton surface the center shows that a spherical deton wave can maintain itself in the case of TNT. It is not known whether this is true in all cases Lutzky (Ref 86) determined the Flow  

Field Behind a Spherical Detonation in TNT Using the Landau—Stanyukovich Equation of State for Detonation Products [See also under Detonation (and Explosion), Spherical and under Detonation, Spherical Wave for the Gaseous Products of Solid Explosives in] 

Detonation Waves, Spherically Symmetric Flaw in the Steady Zone of. See under Detonation Waves Steady-State, Three-Dimensional, Axially Symmetric 

Detonation Wave, Spinning, See under Detonation (and Explosion), Spinning and in Ref 105, listed on p D730 

Detonation Wave, Spread Around Its Initiating Point in High Explosives. 

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The flux-corrected-transport technique was also used by Phillips (1980), who successfully simulated the process of propagation of a detonation wave by a very simple mechanism. The reactive mixture was modeled to release its complete heat of combustion instantaneously after some prescribed temperature was attained by compression. A spherical detonation wave, simulated in this way, showed a correct propagation velocity and Taylor wave shape. 

Rarefaction waves are generated circumferentially at the tube as the detonation leaves then they propagate toward the tube axis, cool the shock-heated gases, and, consequently, increase the reaction induction time. This induced delay decouples the reaction zone from the shock and a deflagration persists. The tube diameter must be large enough so that a core near the tube axis is not quenched and this core can support the development of a spherical detonation wave. 

Motion of the Detonation Products Behind Plane and Spherical Detonation Waves in Solid Explosives , Penn State Uiiv, Dept of Engrg Mechanics Tech Rept 3 (30 Nov 1964) (Dept of Army Contract DA-36-034-ORD-3576RD) 9) M. Lutzky, "The Flow... 

The mixtures were placed in transparent round latex flasks. Initiation was in the center. With their method, it was possible to record spherical detonation waves whose velocities were the same as when these mixtures were detonated in tubes. The waves usually originated very near the ignition source (electric spark or electric primer), but in some cases there was a brief predetonation period... 

Spherical detonation waves can also be produced by condensed expls (solid ot liquid), especially if the charges are spherical in shape and they are initiated in the center. The above discussion of Baum et al applies to both gaseous and condensed expls. Addnl information on spherical detonation of solid explosives can be obtd from the works of Landau 8c Stanyukovich (Ref 2), Jones Miller (Ref 3), Wecken Sc Muecke (Ref 4a), Lutzky (Ref 26), Rudlin (Ref 26a) and Green James (Ref 27)... 

N. Manson F. Ferrie, "Spherical Detonation Waves , 4thSympCombstn(1952)... 

Detonation, TDBP Wave (Taylor- Doring-Burkhardt-Pfriem Wave). Accdg to discussion given by Cook in Chapter 5, under "Theoretical Wave Profiles (Ref 4, pp 92ff), Taylor (Ref 3) studied theoretically the p(x) and W (x) distributions behind plane and spherical detonation waves for gaseous expls and TNT, using the hydrodynamic equation ... 

Eyring et al (Refs 9 22a) postulated that the curved shock front is made up of spherical segmen ts and that behind each segment is the radially divergent flow which occurs behind a spherical deton wave initiated at a point inside an explosive (Taylor, Ref... 

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... 

Dynamics of combustion products behind plane and spherical detonation wave fronts in explosives )... 

An Approximate Solution of the Flow Within the Reaction Zone Behind a Spherical Detonation Wave in TNT, NavWepsRept 7364... 

Some basic work on the formation of spherical detonation waves from explosing gas mixts confined ia ballons was reported. ... 

H. Freiwald H. Ude, Untersuchungen an kugelfbrmigen Detonationswellen in Gasgemischen (Investigations of spherical detonation waves in gas mixtures), pp 663-72... 

Manson, N., Ferrie, F., Contribution to the Study of Spherical Detonation Waves, ... 

Some basic work on the formation of spherical detonation waves from explosing gas mixts confined in ballons was reported. by Freiwald Uhde (Ref 2). Magram in the US earlier studied die effects of expl gases (Ref 1). Many of the first feasibility studies of FAE and FAE weaponization developments were carried out at the US Naval Ordnance Test Station, China Lake, Calif (Refs 3 4)... 

N. Manson and F. Ferrie, Contribution to the Study of Spherical Detonation Waves, in Fourth Symposium (Internat.) on Combustion, The Williams and Wilkins Co., Baltimore, 1953, pp. 486-494. 

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