SUBJECTS detonation wave

The physicochemical properties of explosives are fundamentally equivalent to those of propellants. Explosives are also made of energetic materials such as nitropolymers and composite materials composed of crystalline particles and polymeric materials. TNT, RDX, and HMX are typical energetic crystalline materials used as explosives. Furthermore, when ammonium nitrate (AN) particles are mixed with an oil, an energetic explosive named ANFO (ammonium nitrate fuel oil) is formed. AN with water is also an explosive, named slurry explosive, used in industrial and civil engineering. A difference between the materials used as explosives and propellants is not readily evident. Propellants can be detonated when they are subjected to excess heat energy or mechanical shock. Explosives can be deflagrated steadily without a detonation wave when they are gently heated without mechanical shock. 

Basu J.A. Fay, "Ionization in Detonation Waves , 7thSympCombstn(1958)> pp 277-82 7) Dunkle s Syllabus (1957-1958), pp 387-89 ("Effects of the Ionization in the Shock Front ) (Review of previous work on this subject) (See... 

Detonation, Explosive Wave Shaping by Delayed. M.M. Sultanoff discussed this subject at the Proceedings of the First Symposium on Detonation Wave Shaping (sponsored by Picatinny Arsenal) at the Jet Propulsion Laboratory, Pasadena, California, June 5-7, 1956... 

Detonation Wave One-Dimensional Approximation. This subject was discussed by Lewis Friauf (Ref la) and also in the book of Lewis vonElbe (Ref 66a, p 512-24)... 

Detonation Wave, plate Velocities in Impulse Loading by. This subject was discussed in the paper entitled "Plate Velocities in Impulse Loading by Detonation Waves , presented by RiB.>Clay et al of Univ of Utah at the Symposium on Shock Waves in Process Equipment Annual Meeting of American Institute of Chemical Engineers, Chicago,... 

For more info on this subject see Refs Refs l)R.Brinkley E.B.Wilson, OSRD 1707 (1943) 2)B.L.Hicks et al, JApplPhys 18, 891 (1947) 3)K.P.Staniukovich, DoklAkadN 55, 311 (1947) 4)H.Eyring et al, ChemRevs 45, 69 181 (1949) 5)H.Jones, ProcRoySoc 204, 9-12(1950 6) H.H.Pike R.E.Weir, "The Passage of a Detonation Wave Across the Interface Between Two Explosives , ARE(Armament Research Establishment) Report No 22/50, British Ministry of Supply( 1950XConf)... 

The subject of our study will first of all be the theory of the detonation velocity, the mechanical effects of a detonation wave and, finally and most importantly, the conditions of chemical reaction in the wave. A short summary of the results obtained by the author are given at the end of the book. 

Turning to the detonation of condensed EM we note that in this case the study of the equation of state of a dense gas in which repulsion of molecules is more important than their thermal motion turned out to be non-trivial (see the fundamental work by L. D. Landau and K. P. Stanyukovich).29 Water-filled EM were studied by Yu. B. Khariton.30 At present A. N. Dremin is developing ideas on the specific influence of a shock wave on the kinetics of reaction in an EM.31 For gas-dispersion systems the structure of detonation waves has become the subject of numerous studies related to explosions of coal dust husks in grain elevators, gas suspensions of dust in wood processing, etc.32,33 34 5 Works on gas suspensions have also been published abroad.36,37 In gas suspensions we may expect that the reaction rate is determined by diffusion and depends weakly on the temperature. 

The effect of overpressure on the surface of a structure depends on its natural frequency. For a detonation wave the incident shock wave will be reflected at a higher level, followed by a rarefaction wave. The magnitudes of the resulting multiplication factors are presented in Ref 5 which should be consulted for further discussion of this and related subjects. Flammable gas explns do not normally give rise to amplified reflection waves. A more recent discussion on the characterization and evaluation of accidental explns was published by Strehlow and Baker (Ref 44a)... 

Priming compositions for firearms ammunition are mixtures which, when subjected to percussion, provide a sudden burst of flame that serves to ignite the propellant within the cartridge case. A priming composition must deliver a relatively large volume of hot gases and hot solid particles without the development of a detonating wave. 

As already stated, when a high explosive is subjected to the action of the shock wave whose pressure is somev at below its detonating wave pressure, the shock wave will travel a run-to-detonation distance through the explosive before being transformed into a full detonation wave. The lower the pressure of the shock wave, the longer the distance (or time) to the full detonation. The sensitivity of a given explosive to shock wave initiation is indicated by run-to-detonation distance. 

Under the title "Distant Effect of Detonation , Dr G.R. Loehr [PicArsn Translation No 5 (1956)1 translated from the German the paper by A. Haid entitled "Die Fernwirkung von Detonationen in Explosivstoffe 3, 139-44 (1955). The paper deals with the following subjects a) Formation of a compression shock wave b) Properties of shock waves c) Destructive effect of shock waves... 

Detonation (and Explosion), Effects of Blast and Shock Wave on Structures. As this subject was not discussed in Vol 2 of Encycl, under "BLAST EFFECTS IN AIR, EARTH AND WATER , pp B180-L to B184-R, there is given here a brief description as taken from the book of Robinson (1944), where it is described in detail on pp 45-53... 

In the book of Zel dovich Kompaneets (Ref 45a), the following subjects related to detonation pressure are discussed p 12-13 (Shock compression and isentropic compression) 14 (Static pressure) 27 (Pressure in weak shock waves) 31 (Pressure in shock wave of an ideal gas) 92-8 (Formation of an overcompressed detonation wsve on forcing the detonation in a gas to pass from a large pipe to a narrow one) ... 

In the discussion of the same paper (pp 286-8) M. Norrish suggested generation of shock waves by adiabatic heating of an isolated section of a gas sample by flash irradiation. Thus a H2/O2 mixture with a trace of NO2 as a sensitizer (and no added coolant gas) could be subjected to a high- intensity flash.at one end of a quartz tube, the rest of the tube (to the extent of possibly 5/6) being blacked out. In such a detonation, Thrush (Ref 8a) has observed the emission... 

Detonation, Strong and Weak. This subject is discussed by Evans 8t Ablow (Ref 2, pp 141-42), but prior to this it. is necessary to discuss the existence and uniqueness of classes of reaction waves for specific boundary conditions , as given in the book of Courant 8c Friedrichs (Ref 1, pp 215-22) and in Ref 2... 

This subject is discussed at the beginning of this section entitled DETONATION (AND EXPLOSION) WAVES and in the following Refs 27, 40, 51, 65, 103 104... 

Detonation and Shock Waves, Theory of Point Detonation. This subject is described by Baum et al (Ref 59, Pp 598- 624), under the title "Teoriya Tochechnago Vzryva . 

The minimum shock wave pressure that causes complete detonation of the explosive under test is a measure of shock sensitivity of the explosive and is determined with the help of a gap test . The principle of this test is to subject the explosive under test to the action of a shock wave of known pressure generated by means of a calibrated donor charge and a shock wave pressure attenuator. 

The propagation of shock waves accompanied by an irreversible chemical reaction with substantial release of heat is the subject of the theory of detonation [3-6]. 

Consequently, if we were able to construct a regime in which, beyond the state represented by the point E on the segment DFB where (8) is satisfied (by the end of the chemical reaction), the material were to be subjected to braking and removal of heat, then at the same time there would appear a layer of material with a lowered (due to the lowered temperature) speed of sound, which would protect the detonation front from any additional rarefaction waves. 

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