Initiation shock

5-5 GPa range. Two classic papers published in 1961 by W. C. Davis and coworkers [65,66] used a large body of accumulated experimental results to explain how the basic initiation phenomenon was fundamentally different in homogeneous and heterogeneous composite solid explosives. The fundamental differences are illustrated in Fig. 8. 

Brill and James [47] wrote a beautiful yet cynical paper that examined the problem of low quality or illogical correlations between molecular properties and sensitivity. They focused on a set of four closely related amino-substituted trinitrobenzenes that are often used as model compounds [46] in the sensitivity 

One of the most significant problems with the search for sensitivity predictors lies in the misuse of correlation analysis. It is a fundamental rule of statistical analysis that the data that are used to infer a correlation cannot be used to prove its existence. So if a study of these four substituted benzene compounds suggested that sensitivity is correlated with some spectroscopic transition or some bond parameter, then the existence of this correlation can only be proven by examining its validity using a large number of other materials not used to infer the correlation s existence. A true theory of sensitivity that resulted should be better than one which simply reaffirms the position of four compounds on a sensitivity plot—it should be equally able to tell us the relative sensitivities of new and different explosive compounds and in addition that nonexplosive compounds such as sodium chloride or liquid nitrogen will not explode. 

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Weston, A.M., Kincaid, J.F., James, E., Lee, E.L., Green, L.G., and Walton, J.R., Correlation of the Results of Shock Initiation Tests, in Seventh Symposium (International) on Detonation, NSWC MP 82-334 (edited by Short, J.M.), Naval Surface Weapons Center, While Oak, Silver Spring, MD, 1982, pp. 887-897. 

In their original publications (Ref 28) Campbell et al claimed that the shock initiation process... 

Exptl evidence showing that shock initiation in high density PETN pressings proceeds rather similarly to that in homogenous expls was obtained by the writer (Ref 74, p 219) and by Wackerle and coworkers (Refs 79 94). Fig 10, taken from Ref 74, summarizes the results of an... 

Algebraic expressions for run-up distances, Xj, and times to detonation, tj, for the shock initiation of high density PETN pressings, taken... 

K at P0 = ISOkbar for single crystal PETN and AT = 130°K at 25kbar, and AT = 230°K at 50kbar for PETN at 1.475g/cc. Obviously much, work remains to be done before the mechanism of shock initiation of heterogeneous expls is fully understood... 

Detonation in SP is initiated by shock or by DDT (deflagration to detonation transition). Let us first examine shock initiation, ie, initiation by in-contact or close-by detonation of HE... 

Chemical Aspects of the Shock Initiation of Fuel Droplets , PATR 4153 (1971)... 

Presence of, for example, 5% of methylammonium acetate and 5% of methanol sensitises nitromethane to shock-initiation. 

Berger, J. und Viard, J. Physique des explosifs solides, Dunod, Paris 1962 Dinegar, R. H., Rochester, R. H. und Millican, M. S. The Effect of Specific Surface on Explosion Time of Shock Initiated PETN, Am. Chem. Soc., Div. Fuel Chem. 7 (Nr. 3), 17-27 (1963)... 

FIGURE 8.3 Comparison of measured and calculated NO concentration profiles for a CH4—02—N2 mixture behind reflected shocks. Initial post-shock conditions r= 2960K, P = 3.2 atm (from Bowman [12]). 

In all shock-initiated tests, the probability of a violent incident increased with an increase in the temperature of the aluminum. In many instances, explosions could be obtained even in g/ass-bottomed vessels or vessels with an organic coating. The eiluminum on the bottom would explode violently with completion in about 600 jusec. (There may, however, have been a 1- to 2-msec delay after the detonation of the explosive charge before the large explosion.)... 

A Proposed Mechanism for Shock Initiation of Low Density Granular Explosives , Ptoc... 

Measurements During Shock Initiation of Composition B , Ibid, 855-61 10) B.G. Craig,... 

Interstitial Gas on the Shock Sensitivity of Low Explosive Compacts , Ibid, 349-58(1965) 13) Marjorie W. Evans et al, Shock Initiation of Low-Density Pressing of Ammonium Perchlorate , Ibid, 359-71 14) Donna Price T.P. 

Condensed expls, reaction zone) 8) Baum, Stanyukovich Shekhter(1959), 664-753 (Expln in condensed media) 9) A. Vidart MP 42, 83-144 (I960) (Calcn of characteristics of condensed expls) 10) Andreev Belyaev (I960), 193-210 (Deton of condensed expls) 11) L.G. Bolkhovitinov, DoklAkadN 130, 1044-46(1960) (Low-speed deton of liquid expls) 11a) 3rdONRSymp-Deton(1960), pp 469 98, A.W. Campbell et al, "The Shock Initiation of Detonation in Liquid Explosives 12) R.F. Chaiken, JChemPhys 33, 760(1960) in 3rdONRSymp-Deton(1960), pp 304-08 (Comments on hyper-velocity wave in condensed expls 12a) Zel dovich Kompaneets (I960), Chapter 4 (Detonation in condensed expls) 13)... 

A.W. Campbell et al, PhysFluids 4, 498-510(1961) (Shock initiation of deton in liquid expls) 15a) Ibid, pp 511-22(1961) (Shock initiation in solid expls) 16) R.O. Miller, "Estimating Caloric State Behavior in Condensed-Phase Detonations , pp 65-74 in S.S. Penner F.A. Williams, "Detonation and Two-Phase Flow , Academic Press, NY (1962) 16a) R.F. Chaiken, A Kinetic... 

Mader, "The Hydrodynamic Hot Spot and Shock Initiation of Homogeneous Explosives", LASL Rept LA-2703 (1962) PhysFluids 6,... 

M.C. Chick, "The Effect of Interstitial Gas on the Shock Sensitivity of Low Density Explosive Compacts , 4th ONRSympDeton (1965), pp 349-58 [A small scale gap test, briefly described on pp 350-51, has been used to investigate the role played by interstitial gases in the shock initiation of granular cylindrical charges of HMX (p = 1.14g/cc with 40% voids) and PET tf (p =... 

Chaiken (Ref 5) reported that his prior streak camera studies of the shock initiation to deton of NM indicated the existence of a "hypervelocity wave moving behind the initiating shock front. It was suggested that the deton reaction wave originated be-... 

Hamilton G.L. Schott, Post-Induction Kinetics in Shock-Initiated H2-O2 Reactions , Ibid, pp 635-43 86) R.I. Solou-... 

Seay, "Shock Initiation of Granular Explosives Pressed to Low Density , Ibid, pp 530-35 12) F.J. Warner, "The Initia-... 

Cachia, p 513, he referred to "the clear indication that shock initiation can proceed either by a continuous intensification of the entering shock, or via an intermediate burning phase which may last tens of microseconds . When initiation is achieved by... 

I960) (Promotion of shock initiation by metallic surfaces) 26) Dunkle s Syllabus (1960-1961), p 13-a, 2nd paragraph (Discussion on the work of Eichelberger Sultanoff on sympathetic detonation, listed here as Ref 20) p 13a, last paragraph [Discussion on the works of Cook et al on sympathetic detons, listed here as Ref 19-They called the barrier betw "donor and "receptor a "shock-pass-heat-filter ... 

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