Application to Detonation

We have applied the equation of state to numerous formulations containing the elements C, H, N, and O. We find that the EXP6 equation of state library improves significantly on previous BKW libraries. Its average error in the detonation velocity is somewhat higher than that of JCZS. EXP6, however, is not fit to any detonation data, whereas many adjustable parameters in JCZS were fit to detonation data. 

New experiments are needed to further our imderstanding of the equation of state and kinetics of detonation products. The optical Impulsive Stimulated Light Scattering (ISLS) technique is discussed in general in Ref 

In a fluid sample one longitudinal wave is excited. The impulsively excited acoustic wave induces a temporally and spatially periodic variation in the index of refraction of the sample. A third pulse ( 1 pJ, 20 pm diameter, 80 ps duration) selected from the same Q-switched envelope as the excitation pulses is frequency doubled (A,p = 0.532pm) and delayed by a combination of time of flight and mode lock pulse selection to generate the probe. Observation of the intensity of the Bragg scattering of the probe, by the acoustic or thermo-acoustic grating, as a function of probe delay serves to determine the frequency (v), and hence the adiabatic velocity (c = dv) of the acoustic waves. 

5°C and in order to match as closely as possible the two spectral line shapes. With hydrostatic samples one can measure pressures with a precision of slightly better than 0.01 GPa. A l/4m spectrometer (1200 grooves/mm grating) and 750 bin CCD (11 pm pixel width) gave a dispersion of 2.3 x 10 A/bin. Micro FTIR spectra were taken on a Bruker Optics vector-33 FTIR spectrometer (4cm resolution). 

Liquid formaldehyde is not available commercially, and exists only at low temperatures. Our chemical procedure for producing liquid formaldehyde was as follows Into a dried 500 mL 3-necked round-bottomed fitted with a N2 inlet and outlet, thermocouple, and surrounded by a heating mantle was placed approximately 80g of paraformaldehyde (fills flask 2/3 full). The mixture was heated to decompose the paraformaldehyde with the internal temperature controlled with a thermocouple connected to a temperature controller set at 150 C. The formaldehyde was initially collected (under a slow N2 flow) in a small condensing trap cooled at CO2/ acetone temperature to insure removal of residual water and any low boiling impurities. After about 5 mL of formaldehyde was collected in the trap the outlet tube was coimected to the diamond anvil apparatus, which was kept under a N2 atmosphere and cooled to dry ice/ acetone temperatures. Enough formaldehyde was collected to completely cover the diamond anvil cell ( 20 mL). The cell was opened and then closed to encapsulate the sample. A rhenium gasket was used to radially confine the diamond anvil cell samples. 

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Pure shock waves) 4) G.B. Kistiakowsky, p 951 in Kirk Othmer 5 (1950), pp given in the text (Not included in the 2nd edition) 5) Corner, Ballistics (1950), 100-01 (Corner Noble-Abel equations of state) 6) SAC MS, Ballistics (1951), 18 (Covolume and equation of state of propint gases) 7) Taylor(1952), 34 (Boltzmann and Hirschfelder Roseveare equation of state for the expln products) 69-72 (Rankine-Hugoniot equation of state) 87-98 (Abel, Boltzmann and other equations of state applicable to deton of condensed expls yielding only gaseous products) 114 (Equations of state applicable to deton of condensed expls whose products contain a condensed phase)... 

Equations of state applicable to detonation products of condensed expls 4 D270—D271... 

The Equation of State and Chemistry at Extreme Conditions Applications to Detonation Products... 

Since percussion primers are used for initiation of explosives as well as ignition of propellants in small guns and gas cartridges, and also for purely pyrotechnical initiation such as of pressed delay trains and section charges, the formulations vary with the purpose, though some formulas are said to be equally applicable to detonation or ignition. In other cases, low-violence and low-gas formation are claimed to make the primer especially useful for pyrotechnic ignition. 

M. S. Shaw and J. D. Johnson, The Theory of Dense Molecular Fluid Equations of State with Application to Detonation Products , Eighth Symposium on Detonation, pages 531-539 (1985). 

Decomposition Flame Arresters Above certain minimum pipe diameters, temperatures, and pressures, some gases may propagate decomposition flames in the absence of oxidant. Special in-line arresters have been developed (Fig. 26-27). Both deflagration and detonation flames of acetylene have been arrested by hydrauhc valve arresters, packed beds (which can be additionally water-wetted), and arrays of parallel sintered metal elements. Information on hydraulic and packed-bed arresters can be found in the Compressed Gas Association Pamphlet G1.3, Acetylene Transmission for Chemical Synthesis. Special arresters have also been used for ethylene in 1000- to 1500-psi transmission lines and for ethylene oxide in process units. Since ethylene is not known to detonate in the absence of oxidant, these arresters were designed for in-line deflagration application. 

Concerned mainly with the security of explosives and restncted substances. Applicable to the acquisition, keeping, handling and control of explosives, e.g. blasting explosives, detonators, fuses, ammunitions, propellants, pyrotechnics and fireworks. 

Examining the conditions for the formation and propagation of detonation waves is relevant to special applications of detonations to propulsion as well as safety. 

Ref D. Venable and T.J. Boyd, Jr, PHERMEX Applications to Studies of Detonation Waves and Shock Waves , 4th ONRSympDeton (1965), 639-47 (29 refs are included)... 

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 ballistic mortar and lead block tests use only small amounts of explosive and are not applicable to slurry explosives which are too insensitive to detonate properly under such conditions. For these explosives it is useful to fire larger amounts of several kg under water and measure the period of oscillation of the gas bubble produced. The longer the period the greater the energy of the gas bubble and this part of the total energy of the explosive has been found to correlate well with the blasting effect of the explosive. 

Diazodinitrophenol is a yellow powder, almost insoluble in cold water. It does not detonate when unconfined, but when confined has a velocity of 6900 m s-1 and a density of 1-58 g ml-1. For an initiating explosive it is relatively insensitive to friction and impact, but still is powerful when confined. DDNP has good properties of storage and has found application in detonators, particularly in the U.S.A. 

Reacting Multiple Phase Mixtures Application to the Detonation Properties of PETN. 

Primary explosives differ from secondary explosives in that they undergo a rapid transition from burning to detonation and have the ability to transmit the detonation to less sensitive (but more powerful) secondary explosives. Primary explosives have high degrees of sensitivity to initiation through shock, friction, electric spark, or high temperature, and explode whether confined or unconfined. Some widely used primary explosives include lead azide, silver azide, tetrazene, lead styphnate, mercury fulminate, and diazodinitrophenol. Nuclear weapon applications normally limit the use of primary explosives to lead azide and lead styphnate. 

Over several decades, extensive research has been undertaken on the fundamental theory and the mechanisms involved in detonation. Extensive information on this research is in the literature [10]. But of the three fundamental combustion phenomena — deflagration, explosion, and detonation — only detonation has not found exploitation in practical civilian or military applications to the extent that this phenomenon warrants. This is partly due to the fact that the science and technology involved is very complex due to the intense and fast energy release rates and their interaction with the confinement prescribed by the... 

H) W. Fickett W.W. Wood, The Physics of Fluids 1 (6), 528-34 (Nov-Dec 1958) (Detonation-product equations of state, known as "constant-/ and "constant-)/ , obtained from hydrodynamic data) I) J.J. Erpenbeck D.G. Miller, IEC 51, 329-31 (March 1959) (Semiempirical vapor pressure relation based on Dieterici s equation of state J) K.A. Kobe P.S. Murti, IEC 51, 332 (March 1959) (Ideal critical volumes for generalized correlations) (Application to the Macleod equation of state) Kj) S. Katz et al, jApplPhys 10, 568-76(April 1959) (Hugoniot equation of state of aluminum and steel) K2) S.J. Jacobs, jAmRocketSoc 30, 151(1960) (Review of semi-empirical equations of state)... 

D. Venable T.J. Boyd, Jr, "PHERMEX Applications to Studies of Detonation Waves... 

Shaped charge for perforating oil well casing) 55) Cook (1958), Chapter 10, "Principles of Shaped Charges , which includes History (pp 226-28) Explosive factors in cavity effect (228-29) Application to mass loading in different geometries (229-35) Detonation pressure in nonideal explosives (235-44) Mechanism of linear collapse and jet formation (244-47) Metal-... 

Normal Reflection of Shock and Rarefaction Waves (82-4) Types of Interaction (86) Normal Reflection of Rarefaction (86-7) Normal Refraction of Shock and Rarefaction Waves (87-8) Head-on Collisions (88-9) Oblique Intersections (89 90) Oblique Interactions (90-1) Spherical Shock Waves (97-8) Distinction Between Shock and Detonation Fronts (163-66) Application to Solid Explosives (166-68) Principle of Similarity and Its Application to Shock Waves (307-10) Effects of Ionization in the Shock Front (387-90)... 

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