Detonations spinning

The instability and nonplanar character of the detonation front was first exhibited by Manson [1] and Fay [2] in certain particular cases of detonation propagation, such as fhe "spinning detonations." The multidimensional nature of the detonation front has been established by Voitsekhovskii [3], Denisov and Troshin [4],... 

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

N. Tsuboi, K. Eto, and A.K. Hayashi, Detailed structure of spinning detonation in a circular tube. Combust. Flame, 149, 144-161, 2007. 

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. 

Detonation can also arise spontaneously from combustion when a flame is propagated in very long tubes. For description of this phenomenon, Zel dovich Kompaneets refer to their Chapter 16, which deals with "Spin Detonation ... 

The Three-Dimensional Wave System of Spinning Detonation , Ibid, pp 839-50 890 R. Cheret J. Brossard, "Cylindrical and Spherical Detonations in Gases , Ibid, Paper 84, p 149 (Abstracts only) 89g)... 

Cook (Ref 16, p 143) in discussing the existence of free electrons in combustion flames and gaseous detonations (first mentioned in 1893 by Turpin and then theoretically discussed in 1909 by J.J. Thomson), quoted the paper of Bone et al (Ref 3), who stated that A.E. Malinovskii et al observed in 1924 the presence of free electrons during detonations of benzene-air mixtures and later (1930 8t 1933) of methane-, ethylene-, and acetylene-air mixtures. Bone et al confirmed Malinovskii s results in the case of spinning detonation of a moist 2CO +O2 mixture (Ref 16, p 143)... 

Accdg to Zel dovich Kompaneets (Ref 20, p 170), spin detonation always arises in a pipe of a given diameter for a known composition of the mixture, regardless of susceptibility to initiation, where the distance between L (equal to the distance between bands) proves to be strictly constant. With a change of the inside diameter of the pipe d, the distance L is changed in proportion to the pipe diameter in such a way that the ratio L/d remains constant... 

There have been proposed two hypotheses concerning the nature of detonation spin 1) The effect is elicited by the fact that in a spin detonation the reaction takes place periodically 2) The effect is elicited by the motion of ignition zone ... 

Lewis von Elbe noted in discussion on spinning detonations (Ref 23) that, in an ideal one-dimensional detonation, the... 

Spinning detonation would, therefore, be most likely to occur whenever the induction zone is so thick that the transverse vibrations responsible for the phenomenon are not damped out by the mass flow. This would explain why spin is associated with mixtures near the detonation limits, and disappears in highly detonable mixtures in which induction times are very short and induction zones are very thin... 

Pukhnachev (Ref 26) made a stability analysis of Chapman-Jouguet detonations to clarify the development of spinning detonations. The phenomena leading to them cannot be described by solution of simple hydrodynamic and reaction-kinetic equations for flat detonation fronts. The analysis was based on previous detonation stability analyses by Shchelkin et al with constant supersonic flow postulated along the z-axis at z <0. There is a sharp discontinuity at z=0, followed by the combustion zone. 

Dabora et al (Ref 27) in a study of detonating H2-O2 mixtures surrounded by a compressible medium such as an inert gas, found that in columns of explosive mixture narrower than a limiting width, the velocity decrement reached 8-10% and led to quenching. Some features of a spinning detonation are observed near the limit. 

Macpherson (Ref 31) discussed the three-dimensional wave system of spinning detonation... 

Considerable work on spinning detonation was done in Russia, as can be seen in Refs 5. 6. 7. 10 19. Some of this work was briefly discussed in the book of Zel dovich Kompaneets (Ref 20), nothing on detonation spin is found in Rus books of Baum, Stanyukovich Shekhter (1959) and of Andreev Belyaev (I960). The works of Borisov Kogarko (Ref 25) and of Pukhnachev (Ref 26) appeared later than the book of Zel dovich Kompaneets Refs 1) C. Campbell D.W. Woodhead,... 

C. Campbell A.C. Finch, JCS 1928, 2094 (Deton spin) 3) W.A. Bone et al, TrPhilSoc(London) 228A, 197(1929) 230A, 363(1932) and 235A, 29(1935) [Discussion on detonation spin and on the presence of free electrons in spinning deton waves... 

S.M. Kogarko Ya.B. Zel -dovich, DoklAkadN 63, 553(1948) (Experiments conducted in order to prove the existence of the zone of increased pressure directly behind the shock wave front in spin detonation) (These experiments are also described in Ref 20, pp 183-85)... 

Ya.B.Zel dovich I.Ya. Shlyapintokh, DoklAkadN 65, 871(1949) (The reaction propagation regime in an expl gaseous mixture, being similar in its mechanism to spin detonation, was studied, making use... 

Zel dovich Kompaneets (i960), 170-85 (Spin and spinning detonation) 21) D.H. Edwards Sc T.G. Jones, BritJApplPhys 11, 190-94 (May I960) (Vibration phenomena in detonation waves in hydrogen-oxygen mixtures). 22) Dunkle s Syllabus (1960-1961) p lid (Discussion on work of Fay Opel listed here as Ref 17) 23) B. Lewis ... 

SympDeton (1965) (No papers on spinning detonation) 29) D.H. Edwards et al, JFluidMech 26(2), 321-36(1966) (The structure of the wave front in spinning detonation) 30) J. Brossard et al, Propagation and Vibratory Phenomena of Cylindrical and Expanding Detonation Waves in Gases ,... 

A stability analysis for Chapman-Jfouguet detonations made by Pukhnachev (Ref 6a) to clarify the development of phenomena leading to spinning detonations is discussed under Detonation, Spin (Spinning or Heli-coidal Detonation)... 

Spinning Detonation, Theory of. See Detonation, Spinning Theory of, and in Ref 55b... 

Iitat Actual et Vale ur de la Theorie Hydro-thermodynamique des Explosions et Chocs) (Present status and value of hydro-thermodynamic theory of expins shocks) 55b) J.A. Fay, JChemPhys 20, 942-50 (1951) (Theory of spinning detonation) 56) B. Lewis G. 

Note The observation of an increase in 1 by as. much as 100 m/sec does not imply an increase in particle velocity, W, by a proportional amount the observed slight increase in pitch of the spinning deton could cause a large increase in D with a smaller increase in W... 

The three dimensional wave system in spinning detonation was examined by Mac Pherson (Ref 105)... 

Chu (Ref c) attempted, but did not succeed, to solve the problem of the origin of oscillations. Shchelkin (Ref d) postulated that instability of a deton wave occurs if the induction time is doubled by the drop in temperature of unburned gas. An alternative theory of spinning detonation has been proposed by Predvoditelev (Ref e), according to which helical (low is assumed to occur in the tube. 

It is probable that ignition at bright spots occurs due to shock compression, however combustion of the remaining portion of the substance may be related to turbulent combustion. Satisfaction of the Chapman-Jouguet rule in spin detonation appears probable and is in agreement with experiment, however a rigorous proof of this assertion is lacking. 

Thus, our expectations with respect to the increase of r at the limit and to extension of the limits when the diameter is increased have indeed been realized. However, a detailed photographic study of the wave showed that one of the assumptions, that of uniform reaction over the cross-section, is not justified. In accordance with the observations under laboratory conditions by Shchelkin and his colleagues [3], spin detonation is also found in a wide tube. 

The results obtained must be interpreted from the point of view of the modern theory of spin detonation [4, 5]. In the works cited only the region in which ignition of the gas occurs (the so-called head of the spin or shock wave kink ) was considered. The conditions were found—the speed of the oblique shock wave and corresponding pressure p2 and temperature T2—at the spin head, i.e., the conditions under which ignition occurs in spin detonation. The size of the head b2 and the reaction time r2 at the spin head under these conditions were considered quite small the question of conditions for the existence/feasibility of spin detonation was not posed. 

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