Detonation shock

A detonation shock wave is an abrupt gas dynamic discontinuity across which properties such as gas pressure, density, temperature, and local flow velocities change discontinnonsly. Shockwaves are always characterized by the observation that the wave travels with a velocity that is faster than the local speed of sound in the undisturbed mixtnre ahead of the wave front. The ratio of the wave velocity to the speed of sound is called the Mach number. 

The Chapman-Jongnet (CJ) theory is a one-dimensional model that treats the detonation shock wave as a discontinnity with infinite reaction rate. The conservation equations for mass, momentum, and energy across the one-dimensional wave gives a unique solution for the detonation velocity (CJ velocity) and the state of combustion products immediately behind the detonation wave. Based on the CJ theory it is possible to calculate detonation velocity, detonation pressure, etc. if the gas mixtnre composition is known. The CJ theory does not require any information about the chemical reaction rate (i.e., chemical kinetics). 

Pressures of deflagration or detonation shock waves build upon the existing system pressure at the time of the initial blast. When a deflagration starts and then builds to a detonation, the resulting peak pressure can be quite high because the final pressure of the detonation builds on the peak pressure of the deflagration. 

There are, in general, two types of detonation tests [10,22,24]. In one type of test, the propagation of a detonation shock wave is determined. Examples of methods for this test are the BAM 50/60 test [139], the TNO 50/70 steel tube test [120], and the USA GAP test for solids and liquids [140,141]. 

FIGURE 5.18 Heat of combustion per unit mass (Ahc) and enthalpy rise across detonation shock (Ahs) as a function of hydrogen in oxygen (after Belles [29]). 

Kuhl, A. L., R. E. Ferguson, K. Y. Chien, J. P. Collins, and A. K. Oppenheim. 1995. Gasdynamic model of turbulent combustion in an explosion. Combustion, Detonation, Shock Waves. Zel davich Memorial Proceedings. Eds. A. G. Merzhanov and... 

IEC 47, 1794(1955) (Detailed discussion on Trauzl block method) 15) J.F. Roth, Explosivst 1957, 161-76. PicArsn Translation No 30, by Dr G.R. Loehr (1959) (Ballistic methods for measuring expl power and deton shock) 16) Dunkle s Syllabus (1957-1958), p 257 (Discussion on expression nRTy misnamed "power or "explosive force , whereas a better name is "impetus ) [See "Detonation (and Explosion), Impetus and Available Energy in]... 

In the letter of Jan 22, 1964 (Ref 50), Dunkle pointed out that equating detonation pressure with detonation shock (as has been done by some investigators) is wrong because pressure is a thermodynamic coordinate, while shock is a phenomenon. We might speak of detonation shock pressure, but this would not make it clear whether we mean the "detonation (Chapman-Jouguet or C-J) pressure , or the "pressure in the shock front of the shock wave set... 

Ubbelohde J. Copp, "Detonation Processes in Gases, Liquids and Solids , pp 577-609 of the book "Combustion Processes , edited by B. Lewis et al, Prince-tonUnivPress, Princeton, NJ (1956), 84 refs 38) W.E. Deal, JChemPhys 27, 796-800(1957) (Measurement of Chapman-Jouguet pressure of expls) 38a) D.R. White, JFluidMech 2, 513-14(1957) (On the existence of higher than normal deton pressures) 39) J.F. Roth, Explosivst 1957, 161-76 (Ballistic Methods for Measuring Explosive Power and Detonation Shock) 40) Dunkle s Syllabus, (1957-1958), pp 1-3 (Measurement of detonation pressure) 1 78-81 (Calcn of detonation pressures and densities) ... 

Detonation Principle of Similarity, Its Application in Shock Waves and Scaling Effects. See "Detonation Shock Waves Principle of Similarity, Its Application and Scaling Effects in ... 

Detonation, Sensitivity to Shock. See "Detonation, Shock Sensitivity in ... 

Detonation Shock, Shock Effect, Shock Front, Shock Impulse, Shock Pressure,... 

The difference between a shock front and a shock zone is explained in this writeup under "Detonation Front and Shock Front, Detonation Front and Detonation Zone (See also Ref 4, pp 163-68 Ref 10, p 14a) and under "Detonation, Shock Pressure in ... 

See also "BLAST EFFECTS IN AIR, EARTH AND WATER (V01 2 of Encycl, pp B180-L to B184-R and the following items in this volume "Detonation (and Explosion), Earthwaves from , "Detonation (and Explosion) Effects of Blast and Shock Waves on Structures , "Detonation (and Explosion, Effects Produced in Air, Earth and Water and "DETONATION, SHOCK WAVES ... 

M.A. Cook et al, "Measurements of Detonation Shock and Impact Pressure , 3rd-SympDeton (i960), 357-85 9) J.L. Austing... 

D.N. Schmidt, "Shock Behavior of Some Non-Reacting Shocks , pp 266-76 (See also under DETONATION, SHOCK WAVES IN)... 

Detonation, Shock Impedance and Acoustic Impedance in. Acoustic impedance is the ratio between sound pressure and particle velocity. A sound wave, on reaching a boundary between two media, has part of its energy reflected at the boundary and part transmitted into the 2nd medium. The relationships depend on the values of the acoustic impedance in the two media. Swenson (Ref 2) showed that ... 

Detonation, Shock- or Impact-Loading of Metals, also known as Blast-Loading. 

Detonation, Shock Pass-Heat-Filter (SPHF) in Investigation of. See Ref 40 under DETONATION (AND EXPLOSION), EXPERIMENTAL PROCEDURES and in the following refs ... 

Detonation, Shock Pressure in and Its Measurements. A brief definition of shock pressure is given under Detonation, Shock, Shock Effect, etc. Besides shock pressure, known also as spike pressure, there is also the pressure at the end of the reaction zone (See Detonation, Reaction Zone in). The latter pressure is known as Chapman-Jouguet Pressure or C-J Detonation. It is explained under "Detonation, Chapman-Jouguet Parameters and also under "Detonation (and... 

Detonation, Shock Regime Thermoelectric Effect in. When a shock wave crosses the junction surface of two different metals, there appears between the uncompressed extremities of the metals a difference in potential, the magnitude of which is dependent on the amplitude of the shock wave the nature of the metals. This effect had been first noted in 1959 during the investigation of a thermal elec detector for the recording of temp at the shock front. 

Detonation, Shock Sensitivity in. Sensitivity to shock of explosives, which might also be called "detonability by shock , has been recently measured, mostly by gap tests, using instead of air some plastic materials (such as Lucite) or cardboard for the gap. Some of these tests are described under "DETONATION (AND EXPLOSION), EXPERIMENTAL PROCEDURES IN and also under "DETONATION (AND EXPLOSION), INITIATION BY SHOCK ... 

Detonation, Shock Transmission from Explosive to Metal Plate. Accdg to Cook (Ref 3, p 1H)> R.W. Goranson is credited with suggesting that it is possible to determine the p(x), W(x) and p(x) distribution in the detonation wave by studying the characteristics of the shock wave transmitted from the explosive into a thin metal plate in shock loading of the plate by a detonation wave. In this theory, when a plane detonation wave strikes a metal plate at normal incidence, a shock wave is transmitted into the plate and another is reflected back into the incident wave such. as to give a pressure-distance profile like that illustrated in Fig 5.17 [reproduced by Cook from the paper of Walsh Christian (Ref 1)]. 

Detonation, Shock Wave Principle of Similarity, Its Application and Sea ling... 

The whole round may be fired with a series of delay caps as indicated in Ref 4, p 347 [See also Detonation, Shock Wave (or Stress Wave) Fracturing of Rock in]... 

Calculations of the flow field behind the detonation shock were carried out on an IBM-7090 electronic computer for TNT at initial densities of 1.625, 1.59, 1.45,... 

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