Combustion of nitramine propellant

Cohen, N. S and Price, C. F., Combustion of Nitramine Propellants, AIAA... 

A. Analytical Models of Propellant Combustion and Detonation 57) N.S. Cohen C.F. Price, Combustion of Nitramine Propellants , JSpacecraft -Rockets 12 (10), 608-12 (1975) CA 84,... 

Modeling Development of Steady-State Combustion of Nitramine Propellants... 

Studies on the physical properties, sublimation, decomposition, ignition, and self-deflagration of nitramine propellants conducted prior to 1984 are summarized by Boggs [44] and Fifer [45], and the state of understanding of steady-state combustion of nitramine propellants up to 1990 is given by Alexander et al. [46]. A summary of the latest development is covered in a volume edited by Yang et al. [47]. 

T Combustion of Nitramine Composite Propellants, AlAA/SAE/ASME 17th Joint Propulsion Conference, July 27-29th, Colorado Springs, Colorado, AIAA-81-1582, 1981. 

Kubota, N., Kuwahara, T., Yano, Y, Takizuka, M., and Fukuda, T., Unstable Combustion of Nitramine/Ammonium Perchlorate Composite Propellants, AlAA-81-1523, AlAA, New York (1981). 

The burning surface of an HMX propellant only becomes covered with carbonaceous materials when the propellant is catalyzed with both LiF and C. This surface structure is similar to the burning surface of an H MX propellant catalyzed with a lead compound and C. The results indicate that the combustion mode and the action of LiF are the same as those resulting from the use of lead compounds to produce super-rate and plateau burning of nitramine propellants. 

Kumar, R.N., and Stand, L.D. (1975) Combustion problems of nitramine propellants. Proc. 13th Aero. Sci. Meeting, AIAA, Pasadena, 1975. 

Kubota N., Takizuka M. and Fukada T., "Combustion of Nitramine Composite Propellants", ALAA Paper No. 81, 1587 (1981)... 

Modeling Development of Combustion of Nitramine/GAP Pseudo-Propellants... 

The theoretical model and numerical method outlined in the above sections were implemented to study steady-state combustion of nitramine monopropellants [33.34], laser-induced ignition of RDX [39,40], and steady-state combustion of nitramine/GAP pseudo-propellants [37-39]. The analyses were carried out over a broad range of operating conditions. Various important burning and ignition characteristics were investigated systematically, with emphasis placed on the detailed flame structure and the effect of the subsurface two-phase layer on propellant deflagration. 

Wormhoudt J., Kebabian P L., and Kolb C. E., Embedded infrared fiber optic absorption studies of nitramine propellant strand burning. Combust. Flam, 111, 73-86, 1997. 

Oxidizers. The characteristics of the oxidizer affect the baUistic and mechanical properties of a composite propellant as well as the processibihty. Oxidizers are selected to provide the best combination of available oxygen, high density, low heat of formation, and maximum gas volume in reaction with binders. Increases in oxidizer content increase the density, the adiabatic flame temperature, and the specific impulse of a propellant up to a maximum. The most commonly used inorganic oxidizer in both composite and nitroceUulose-based rocket propellant is ammonium perchlorate. The primary combustion products of an ammonium perchlorate propellant and a polymeric binder containing C, H, and O are CO2, H2, O2, and HCl. Ammonium nitrate has been used in slow burning propellants, and where a smokeless exhaust is requited. Nitramines such as RDX and HMX have also been used where maximum energy is essential. 

Fifer, R. L., Chemistry of Nitrate Ester and Nitramine Propellants, Fundamentals of Solid-Propellant Combustion (Eds. Kuo, K. K., and Summerfield, M.), Progress in Astronautics and Aeronautics, Vol. 90, Chapter 4, AIAA, New York, 1984. 

The combustion wave structure of RDX composite propellants is homogeneous and the temperature in the solid phase and in the gas phase increases relatively smoothly as compared with AP composite propellants. The temperature increases rapidly on and just above the burning surface (in the dark zone near the burning surface) and so the temperature gradient at the burning surface is high. The temperature in the dark zone increases slowly. However, the temperature increases rapidly once more at the luminous flame front. The combustion wave structure of RDX and HMX composite propellants composed of nitramines and hydrocarbon polymers is thus very similar to that of double-base propellants composed of nitrate esters.[1 1... 

When some portion of the AP particles contained within an AP composite propellant is replaced with nitramine particles, an AP-nitramine composite propellan-tis formulated. However, the specific impulse is reduced because there is an insufficient supply of oxidizer to the fuel components, i. e., the composition becomes fuel-rich. The adiabatic flame temperature is also reduced as the mass fraction of nitramine is increased. Fig. 7.49 shows the results of theoretical calculations of and Tf for AP-RDX composite propellants as a function of Irdx- Th propellants are composed of jjxpb(0-13) and the chamber pressure is 7.0 MPa with an optimum expansion to 0.1 MPa. Both I p and T)-decrease with increasing Irdx- The molecular mass of the combustion products also decreases with increasing Irdx due to the production of Hj by the decomposition of RDX. It is evident that no excess oxidizer fragments are available to oxidize this H2. 

Similar to nitramine composite propellants and TAGN composite propellants, AN composite propellants produce halogen-free combustion products and thus represent smokeless propellants. However, their ballistic properties are inferior to those of other composite propellants the burning rate is too low and the pressure exponent is too high to permit fabrication of rocket propellant grains. In addition, the mechanical properties of AN composite propellants vary with temperature due to the phase transitions of AN particles. 

Kubota, N Combustion Mechanisms of Nitramine Composite Propellants, 18th Symposium (International) on Combustion, The Combustion Institute, Pittsburgh, PA (1981), pp. 187-194. 

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