Detonations gaseous

The work done by pressure per unit area, per unit time on a mass of unit cross-sectional area of the zone is p0D -p(D-u). For a unit mass of products of detonation (gaseous), this becomes, after substituting the value D-u from eq 1 and dividing both sides by p0D ... 

Both RDX and HMX are stable, crystalline soHds, somewhat less sensitive to impact than PETN. Both may be handled with no physiological effect if appropriate precautions are taken to assure cleanliness of operations. Both RDX and HMX detonate to form mostiy gaseous, low molecular weight products and some intermediate formation of soHd carbons. The calculated molar detonation products of RDX are 3.00 H2O, 3.00 N2, 1.49 CO2, and 0.02 CO. RDX has been stored for as long as 10 months at 85°C without perceptible deterioration. 

Liquid and Solid Acetylene. Both the Hquid and the soHd have the properties of a high explosive when initiated by detonators or by detonation of adjoining gaseous acetylene (85). At temperatures near the freezing point neither form is easily made to explode by heat, impact, or friction, but initiation becomes easier as the temperature of the Hquid is raised. Violent explosions result from exposure to mild thermal sources at temperatures approaching room temperature. 

Source Nettleton, M.A. 1987. Gaseous Detonations Their Nature, Ejfects, and Control. Chapman and Hall, New York, NY. 

Matsui, H., and J. H. S. Lee. 1979. On the measure of relative detonation hazards of gaseous fuel-oxygen and air mixtures. Seventeenth Symposium (International) on Combustion, pp. 1269-1280. Pittsburgh, PA The Combustion Institute. 

The investigators found that overpressures from the evaporating liquid compared well with those resulting from gaseous detonations of the same energy. 

Nitrogen Triiodide. NI3, mw 394.77, N 3.55%, blk powd, mp (explds), bp (subl in vac). Insol in cold w, decomps in hot w sol in aq Na2S203 and KCNS. Prepd by the action of gaseous NH3 on solid KIBr2, foilowed by rapid w washing (Refs 1,4, 10 11). NI3 must be kept ether wet. When dry, the slightest shock, vibration, temp rise, air draft, etc, will cause it to detonate (Refs 14 15). Under vac, dry NI3 detonates at pressures under 2xlG 3cm. Over this press simple decompn occurs with the evolution of I2 (Refs 7-9)... 

Tellurium Nitride. Te3N4, mw 438.87, N 9.58%, yellow amorph powd, mp (explds above 200° or when quickly heated). Decompd by w (under vac the heat of soln causes deton). Insol in aq ammonia dil acet ac. Prepd by reacting gaseous ammonia with TeCl4 at —15° Te3N4 is unaffected by heating to 150°. 

Nitrogen Triiodide, NI3, mw 394.77, N 3.5% a black powd, detons when dry, exposed to light, or an elec spark (Refs 8 10) Qf 35kcal/mole (Ref 7). It is formed by the interaction of free 1 or I3" on liq, gaseous, or aq ammonia (Refs 1, 8 10). N triiodide forms a series of solvates with excess ammonia NI3.NH3) bright red needles, explds when dry (Ref 2). 

Toxicity and Hazards. The odor cf ozone can be detected in concn as low as several parts per hundred million by vol (pphm). The threshold limit value (TLV) is O.lppmor 0.2mg/m3 its toxic dose level (TDL), 50% kill concn is 2ppm (Ref 6) Pure 100% liq ozone may be kept safely at 90°K (cooled by liq oxygen) for indefinite periods of time, but the smallest provocation, such as a spark or fast warming, even only up to bp (161°K), causes detonation. The evapn of liq ozone, for example, in the process of the prepn of pure gaseous ozone is, therefore, a dangerous procedure (Ref 3, p 224)... 

Two-phase detonations involving fuel drops or solid particles and a gaseous oxidizer have been observed (Refs 8, 9 11). Detonations in fuel drop and gaseous (air or pure oxygen) mixts have been studied in greater detail because of... 

Solid particle-gaseous oxidizer systems have been studied because of applications to propints and expls (Refs 5 14), and hazards due to dust explns (Refs 1,3, 4, 6, 7, 10 15). Strauss (Ref 9) reported on a heterogeneous detonation in a solid particle and gaseous oxidizer mixt the study concerned A1 powder and pure oxygen in a tube. Detonations initiated, by a weak source were obtained in mixts contg 45-60% fuel by mass. Measured characteristics of the detonations agreed with theoretical calcns within about 10%, and detonation pressures of up to 31 atms were observed. With regard to solid particle-air mixts, detonations have not been reported only conditions for expln have been studied (Ref 2)... 

The increase in volume as gaseous products are formed in a chemical reaction is even larger if several gas molecules are produced from each reactant molecule, such as the formation of CO and CO, from a solid fuel (Fig. 4.17). Lead azide, Pb(N3)2, which is used as a detonator for explosives, suddenly releases a large volume of nitrogen gas when it is struck ... 

Oppenheim, A.K. and Stern, R.A., On the development of gaseous detonation - analysis of wave phenomena. Proc. Combust. Inst., 7, 837, 1959. 

Egerton, A. and Gates, S.F., On detonation in gaseous mixtures at high initial pressures and temperatures, Proc. R. Soc., Lond. A, 114,152,1927. 

Schelkin, K.I. and Sokolik, A.S., Detonation in gaseous mixtures, Soviet. Zhurn. Phys. Chem., 10, 479,1937. 

Thus, the elementary cellular structure could be regarded as an intrinsic characteristic of fhe detonation in a mixture at given initial composition, temperature, and pressure. The dimension of X is of fhe order of magnitude of millimeters or less for gaseous mixfures with oxygen, but several centimeters for less sensitive mixtures (even larger, for methane/air af afmospheric pressure). It decreases when the initial pressure increases. Its variation with the initial temperature is more complicated and depends on the value of fhe reduced activation energy of fhe chemical reactions. The value of... 

Yu.N. Denisov and Ya.K. Troshin, Pulsating and spinning detonation of gaseous mixtures in tubes. Doklady Akad. Nauk. SSSR, 125,110-113,1959. 

D.R. White, Turbulent structure of gaseous detonation, Phys. Fluids, 4(4), 465-480,1961. 

K.I. Schchelkin and Ya.K. Troshin, Non stationary phenomena in the gaseous detonation front. Combust. Flame, 7, 143-151, 1963. 

S.U. Schoffel and F. Ebert, Numerical analyses concerning the spatial dynamics of an initially plane gaseous ZND detonation. AIAA Progr. Astron. Aeron., 114, 3-31,1988. 

M.I. Radulescu and J.H.S. Lee, The failure mechanism of gaseous detonations Experiments in porous wall tubes. Combust. Rame, 131, 29-46,2002. 

I.O. Moen, A. Sulmistras, G.O. Thomas, D.J. Bjerketvedt, and PA. Thibault. Influence of regularity on the behaviour of gaseous detonations. Prog. Astron. Aeron., 106, 220-243,1986. 

M.-O. Sturtzer, N. Lamoureux, C. Matignon, D. Desbordes et H.-N. Presles, On the origin of the double cellular structure of the detonation in gaseous nitromethane and its mixtures with oxygen. Shock Waves, 14(1-2), 45-51, 2005. 

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