Detonation transmission

Bjerketvedt, D., and O. K. Sonju. 1984. Detonation transmission across an inert region. Progress in Astronautics and Aeroruiutics. 95, AIAA Inc., New York. 

Soot patterns of detonation transmission from a tube through a cone (=c = 25°) in a C2H2 + 2.5 O2 mixture at 30 mbar initial pressure. (Courtesy of V. Guilly.)... 

In Chapter 8.5, B. Veyssiere exposes the state of knowledge in detonations. Particular features of the complex multidimensional structure of detonations are presented in relation with the recent results obtained either by nonintrusive optical diagnostics or numerical simulations from high performance calculations. The role of transverse waves in detonation propagation, the existence of correlations between the characteristic dimension of the cellular structure and the critical conditions for detonation initiation and detonation transmission, and the influence of the nonmonotonous heat release process behind the front are examined. Recent developments in the study of spinning detonations are also discussed. 

A detonator, in the form of explosive plates made with tetryl then a screen made of cellulose acetate plates is placed in a wooden container. A 26 mm diameter cylinder full of the substance to be analysed is placed on the screen, and finally a steel plate on top of the cylinder is added. If the substance transmits the detonation, the steel plate will be pierced and not projected. Piercing serves as an indicator of detonation transmission. The number of cellulose acetate disks needed between the sample and the detonator to prevent the detonation from being transmitted is found. Only one is needed for most chemical substances, but with m-dinitrobenzene, 240 are required. 

Ability to Propagate Detonation Transmission of Detonation or Extent of Propagation of Explosion. See Vol 1, p VII... 

Table 13.6 giving average air-gap initiation induction time data taken from BRL Rept 865(1953) of M. Sultanoff 8 R.A. Bailey and the shock velocity V computed by M.A. Cook] 19) M.A. Cook et al, PrRoySoc 246A, 281-83 (1958) (Deflagration to detonation transmission in solid and liquid expls) 20) R.J. Eichelberger... 

Ability to Propagate Detonation Transmission of Detonation or Extent of Propagation of Explosion. The prop erty of an expl to conduct detonation, which has been started by an initiator, to neighboring layers is depend ent on the props of the expl mainly velocity of deton and on some other factors(such as confinement, thickness of layer, diam of charge, density of packing, and temp) (Ref 1,3,4,5 6)- In some substs(such as AN), the deton wave might easily die out(or dampen) if the optimum conditions for propagation are not fulfilled... 

Crawford bomb 66 cresylite = mixture of trinitrocresol and picric acid (french) crimping 66 critical diameter 66 CR-propellants = RDX containing rifle powders (USA) cross section ratio -> propellant area ratio 269 crusher 149 362 C.TD. = coefficient of detonation transmission (coefficient de self exitation) (french) 87 CTPB = carboxyl-terminated polybutadiene (USA) 61 329 cumulative priming 66 c.u.p. = coefficient d utilisation pratique (french) 198 cuprene 52 cupric salicylate 163 curing 67... 

The resulting transmission distance is reported as the coefficient of detonation transmission (Koeffizient der Detonationsiibertragung coefficient de transmission de la detonation, C. T. D.) and should be the arithmetic mean of three positive and negative results obtained in successive trials. 

A number of practically important phenomena associated with detonations pose fundamentally more diflicult theoretical problems than those addressed above. These include the initiation of detonations, transmission of a detonation from confined to unconfined spaces, quenching of a detonation, and limits of detonability. Discussion of these phenomena may conveniently be introduced by considering quenching of detonations first. 

Figure 3.10 Results for the 2D diffraction geometry (main combustor — stoichiometric C2H4-air Yo = 5.08 cm initial pressure 100 kPa and initial temperature 283 K) 1 — successful and 2 — unsuccessful detonation transmission. At = 0.4 uncertainty is 0.1 and at y) = 1.4 uncertainty is 0.04...

Figure 3.10 summarizes the successful and unsuccessful test conditions for which detonation transmission occurred for the ethylene-air mixtures. 

Oran, E.S., D. A. Jones, and M. Sichel. 1992. Numerical simulations of detonation transmission. Proc. Royal Society London A 436 267-97. 

Li, C., and K. Kailasanath. 2000. Detonation transmission and transition in channels of different sizes. Combustion Institute Proceedings 28 603-9. 

Additives Amount (%) Viscosity (n) Btisance (mm) Explosion velocity (m/s) Strength (mL) Detonation transmission distance (cm)... 

No. Content of nitromethane X 100 Content of methanol X 100 Content of sensitizer x 100 Ratio of sensitizer to nitromethane X 100 Diaphragm detonation transmission distance /mm Increase of detonation transmission distance /mm... 

The liquid explosives mixture of trinitroethanol orthocarbonate and nitroalkanes have decent chemical stability, which allows them to be stored in glassware for 6 month at room temperature, or for 5 days at 60 °C. In these cases, neither decomposition nor change of explosive properties was observed. The density and detonation velocity of such explosives are close to nitroglycerine, and they can be detonated by No.6 detonators to afford stable detonation transmission with critical diameter less than 4 mm. In addition, their impact sensitivity is also very low, and... 

More detailed study of the transmission of detonation through the air also includes the determination of the functional relationship between the key parameters in the transmission of detonation the performance and the mass of the donor charge and the distance at wfiich detonation transmission occurs under defined testing conditions. The influence of other parameters such as donor shape, existence, and kind of donor confinement can also be included into the study. 

Critical diameter of detonation transmission (CDD) The minimum diameter of... 

What is the effect of temperature on the conditions for hot jet initiation and detonation transmission ... 

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