Burning mechanism

J. A. Stein, P. L. Stang, and M. Summerfield, The Burning Mechanism ofMmmonium Perchlorate-Based Composite Propellants, Aerospace and Mechanical Sciences Report 830, Princeton University, N.J., 1969. 

When BlkPdr is used as a pressed grain, surface normal burning rates can be defined. These studies continue as an important tool in examining the complexities of the burning mechanism. These and other properties of various BlkPdrs have been compared (Ref 72), as has the temp dependence of the burning rates. The enormous volume of published data deals, however, only with conventional, mill process, powder, while the corresponding data on the jet mill powder await the completion of ongoing studies... 

A Survey of the Burning Mechanism of Delay -Relay Columns , PATR 3047 (1964)... 

The burning mechanism of composite propellants differs from that described above. There is no exothermic reaction which can lead to a self-sustaining fizz zone. Instead, the first process appears to be the softening and breakdown of the organic binder/fuel which surrounds the ammonium perchlorate particles. Particles of propellant become detached and enter the flame. The binder is pyrolysed and the ammonium perchlorate broken down, initially to ammonia and perchloric acid. The main chemical reaction is thus in the gas phase, between the initial dissociation products. 

The input requirements for post-flashover types of models can be quite broad. Besides the compartment and vent dimensions, detailed fuel combustion characteristics are often needed. The fuel characteristics include the fraction of carbon, hydrogen, nitrogen, and oxygen that make up the fuel, the burning efficiency, and the quantity of fuel available for burning. Mechanical ventilation flow rates and the material properties of the compartment boundaries may be necessary. Some models can account for the heat transfer through the boundaries in detail, and may even allow the user to supply time-dependent material properties. An example of a post-flashover fire model is COMPF (Babrauskas, 1979). 

Takahashi, F., I. J. Heilweil, and F.L. Dryer. 1989. Disruptive burning mechanism of free slurry droplets. Combustion Science Technology 65 151-65. 

Summerfield, M., Sutherland, G. S., Webb, W. J., Taback, H. J., and Hall, K. P., The Burning Mechanism of Ammonium Perchlorate Propellants, ARS Progress in Astronautics and Rocketry, Vol. 1, Solid Propellant Rocket Research, Academic Press, New York (1950), pp. 141-182. 

Steinz, J. A., Stang, P. L., and Summer-field, M., The Burning Mechanism of Ammonium Perchlorate-Based Composite Solid Propellants, AMS Report No. 830, Aerospace and Mechanical Sciences,... 

Ishihara, A., and Kubota, N., Erosive Burning Mechanism of Double-Base Propellants, 21 St Symposium (International) on Combustion, The Combustion Institute, Pittsburgh, PA (1986), pp. 1975-1981. 

A. Jaumotte, "Remarks on the Burning Mechanism and Erosive Burning of Ammonium Perchlorate Propellants , Ibid, pp 689-93 G2) G.K. Adams et al, "Combustion of Propellants Based on Ammonium Perchlorate , Ibid, p 693-705 Hj) J.Hershkowitz, F. Schwartz J.V.R. Kaufman, "Combustion of Loose Granular Mixtures of Potassium Perchlorate and Aluminum , Ibid, pp 720-27 H2) L.A. Dickinson et al, "Erosive Burning of Polyurethane Propellants in Rocket Engines , Ibid, pp 754-59 H ) S. Kumagai... 

Very little is known about the burning mechanism of these mixtures. There is a two-temperature theory of propellant combustion [2, 3]. 

Extensive research on the burning mechanism of a mixture containing ammonium nitrate has been reported by Chaiken [2] and Andersen, Bills, Mishuck, Moe and Schultz [3]. 

In summary, we have two pieces of indirect evidence for the operation of the envelope burning mechanism in upper AGB stars, but no direct measurement of the 14N abundance in these stars. The importance of the operation of the envelope burning mechanism is that it provides a method of producing primary nitrogen. 

The burning of composite rocket proplnts is more complicated because they contain many ingredients. Several oxidizers and many fuel binders are used to formulate composite compos. The burning of this class of comparatively recent proplnts has not been as well explored as the older NC-NG-base proplnts. Both Geckler(Ref 21a) and Huggett(Ref 24,p 565) present a good review of the burning mechanism as it is understood today(see also Ref 25,pp 100-1)... 

The burning mechanism is proposed to be similar to the mechanism for thermal decomposition. The low-pressure burning is dominated by the decomposition of ADN to AN and N2O [18]. ADN is therefore viewed as a stronger oxidant than AP with the potential to give a higher specific impulse in propulsion. The replacement of AP by ADN in metal fuels gives an energy increase of 10-20% based on theoretical studies... 

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