COMBUSTION OF SOLID PROPELLANTS

Solid propellants are solid materials that are capable of experiencing exothermic reactions without the addition of any other reactants. They are employed mainly as propellants for rocket vehicles and as propelling charges for projectiles in guns. It is intended that the propellants will deflagrate, because a detonation would be damaging. Therefore, sensitive explosives generally are not employed as solid propellants solid-propellant formulations must be sufficiently metastable to resist transition to detonation. 

There are a number of useful background references on solid propellants and their combustion. Most books on rocket propulsion devote at least one chapter to solid propellants [l]-[5]. No less than three books [6] [8] have been concerned solely with solid-propellant topics, the last [8] being a 700-page text on the subject. Readers may consult this literature for more detailed information. 

Since the processes described above occur in series, the slowest processes may be expected to govern the overall burning rate. A number of different burning-velocity formulas may therefore be obtained, depending on which processes are dominant. We shall first discuss interface processes and then consider spatially distributed processes in different phases. 

Let us consider the case in which the burning rate is determined by the rate at which molecules from the condensed phase enter the gas. We shall focus our attention on the process occurring at the interface x = 0. Transition-state theory (Appendix B) provides information concerning the rate of this gasification process. 

Solid propellants generally contain a number of different chemical species, each of which may gasify by processes of varying complexity. However, for illustrative purposes, we shall study the simplest case of a one-component condensed phase that sublimes in a one-step, unimolecular process  

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An Optical Bomb Study of the Combustion of Solid Propellants in High Acceleration Fields , Final Tech Rept, Contract N00014-67-C 0455, Atlantic Research Corp, Alexandria (1969) 9) R.W. Bryant R. Gledhill, Effect of Variations in Composition on Physical Properties of... 

Performance Analysis of a Family of Solid Propellants with Details of the Computer Programme and the Theoretical Method Used , Rept No RPE TN 225, Westcott (Engl) (1963) 6) S.A. Johnson et al, Research on Combustion of Solid Propellants , Rept No 641Q3, Contract DA-04-495-AMC-239(R), Lockheed Proplsn Co, Redlands(1964) 7) R.L.Coates, Research... 

Huggett, C., Combustion of Solid Propellants, Combustion Processes, High-Speed Aerodynamics and Jet Propulsion Series, Vol. 2, Princeton University Press, Princeton, NJ, 1956, pp. 514-574. 

M. Mochizuki, High-Altitude Combustion of Solid Propellant Rockets , KKK26 (4),... 

C. Huggett, Combustion of Solid Propellants, Section M in Combustion Processes, Ed. B. Lewis, R. N. Pease and H. S. Taylor, Princeton University Press, Princeton, N.Y., 1956. 

Energetic Parameters 1) N. Masao et al, Fundamental Studies on Combustion of Solid Propellants II. Burning Velocities of Multi-Component Fuel , KogyoKayakuKyokaishi 27 (5), 295-301 (1966) CA 66,67463 (1967) [The results of these studies indicate that the burning rate of a stoichiometric mixt of ethylene-air is reduced by 27% when 20% of the ethylene is replaced by vinyl ethylene. Also, that the burning rate of a stoichiometric mixt of vinyl ethylene-air is changed slightly even if 40% of the vinyl ethylene is replaced by ethylene. In addn, the authors report that the effect of... 

The Mechanism of Combustion of Solid Propellants in "Selected Combustion Problems-Fundamentals and Aeronautical Applications , AGARD Publication, Butterworths, London(1954) 22)S.S. Penner P.P.Datner, "Combustion Problems in Liquid-Fuel Rocket Engines , in 5th Symposium on Combustion, Reinhold, NY(1955), 11-28(A review with 84 refs) 22 a)Anon, "Military Explosives , TM 9-1910(1955), 229 31 22b)L. 

Princeton Univ Press, Princeton, NJ(1956),pp 470-513(70 refs) 24)C.Hugget, "Combustion of Solid Propellants , in the above book by Lewis et al,pp 514-74(98 refs) 25)F.A.Warren, "Rocket Propellants , Reinhold, NY(1958), 88-107 l37-40(Burning and burning rate of rocket propellants) 26)J.Taylor, "Solid Propellant and Exothermic Compositions , Interscience, NY(1959), 100-4(Burning rate of rocket proplnts) 27)J. 

J. Comer, PrRoySoc 197A, 90 106(1949) 6)Corner, Ballistics(1950), 42ff 7)Symposium on Kinetics of Propellants, JPhysChem 54, 847-954(1950) 8)R.D. Geckler, "The Mechanism of Combustion of Solid Propellants , in "Selected Combustion Problems-Fundamentals and Aeronautical Applications ,... 

AGARD Publications, Butterworths, London (1954), 289 339 9)C. Huggett, "Combustion of Solid Propellants in Vol 2 of B. Lewis et al, Editors, "High-Speed Aeorodynamics and Jet Propulsion Combustion Process , Princeton Univ Press, Princeton, N.J.(1956), 514-74 10)M. Summerfield et al, Jet Propul-... 

Art of Combustion of Solid Propellants, US Naval Ord Test Station, China Lake, Calf... 

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