Propulsion

ADN and compositions of ADN have been shown to be able to undergo self-sustained combustion with higher burn rates than the commonly used oxidizer AP. A basic study showed that the bum rate for compressed ADN was 7.4 mm/s at the sub-atmospheric pressure of 0.2 MPa and 54 mm/s at 6 MPa. Since ADN has a surplus of oxygen, its burn rate increases if a carbon source is added. The low-pressure burning is then expanded down to 0.02 MPa. The burn rate for a mixture of ADN and paraffin in the ratio 90 10 has been determined to be 50 mm/s at 7 MPa with a burn rate coefficient of 0.8 and a flame temperature of 2960 [17]. 

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 

Thiokol Corporation has a patent that covers the use of ADN in rocket compositions together with energetic binders and aluminum as fuel. The patent also covers other salts of dinitramides with nitrogen rich organic bases such as tetrazoles [21]. 

As mentioned earlier, ADN was probably used in rocket propulsion for strategic missiles in the former Soviet Union. Even though Russian researchers have published much scientific work on ADN since then, there have been no descriptions of the formulations that were used. 

In Europe, ADN is studied as an environmentally-friendly alternative to AP in space programs. When AP-based rockets are used, they produce enormous volumes of hydrogen chloride, which is harmful due to its acidic and corrosive character. Also other chlorine derivatives are formed which are toxic and are likely to contribute to the destruction of the 

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The most widely used product is TRO (TR for turbo-reactor) or JP8 (JP for Jet Propulsion), still designated by the NATO symbols F34 and F35. In the United States, the corresponding fuel is called Jet Al. The military sometimes still uses a more volatile jet fuel called TR4, JP4, Jet B, F45 or F40. The preceding terms correspond to slight variations and it would be superfluous to describe them here. 

Practical experience has shown that, depending on the field of application, a considerable reduction in inspection costs can be had when opting for radioscopy rather than radiography. By comparison with film technique, the inspection time of turbine blades for aircraft jet propulsion engines is reduced by 45% to 60%. When adding film costs, approximately DM 450.000,- can be saved per year /3/. As far as... 

The metal has recently found application in ion propulsion systems. Cesium is used in atomic clocks, which are accurate to 5 s in 300 years. Its chief compounds are the chloride and the nitrate. 

Another even more significant use of methyl alcohol can be as a fuel in its own right in fuel cells. In recent years, in cooperation with Caltech s Jet Propulsion Laboratory (JPL), we have developed an efficient new type of fuel cell that uses methyl alcohol directly to produce electricity without the need to first catalytically convert it to produce hydrogen. 

J. G. Baet2, Characterisation of Advanced Solid Pocket No ffe Materials (SAMSO-TR-75-301), Air Eorce Rocket Propulsion Laboratories, Edwards AEB, Calif., Dec. 1975. 

SiHcon nitride (see Nitrides) is a key material for stmctural ceramic appHcations in environments of high mechanical and thermal stress such as in vehicular propulsion engines. Properties which make this material uniquely suitable are high mechanical strength at room and elevated temperatures, good oxidation and creep resistance at high temperatures, high thermal shock resistance, exceUent abrasion and corrosion resistance, low density, and, consequently, a low moment of inertia. Additionally, siHcon nitride is made from abundant raw materials. 

M. W. Beckstead and co-workers, "Convective Combustion Modelling AppHed to Deflagation Detonation Transition," in Proceedings of the 12th JANNAF Combustion Meeting, Pub. No. 273, Chemical Propulsion Information Agency (CPIA), Johns Hopkins University, Laurel, Md., 1975. 

S. Iyer and co-workers, "New High Energy Density Materials for Propellant AppHcations," in 5th International Gun Propellant and Propulsion Symposium, ARDEC, Picatinny Arsenal, N.J., Nov. 1991, pp. 18—21. 

R. D. Lynch and co-workers, "Characteri2ation of Insensitive High Explosives Developed with Propellant Technology," in Proc. 1990JANNAF Propulsion Meeting VIII, 3-5 CPIA Pubhcation 550, CPIA, Laurel, Md., Oct. 1990, pp. 3—5. 

The procedures used for estimating the service life of solid rocket and gun propulsion systems include physical and chemical tests after storage at elevated temperatures under simulated field conditions, modeling and simulation of propellant strains and bond tine characteristics, measurements of stabilizer content, periodic surveillance tests of systems received after storage in the field, and extrapolation of the service life from the detailed data obtained (21—33). 

R. Muracarf and L. L. Taylor, The Hygroscopicity ofTithium and Mmmonium Nitrates and Perchlorates, Progress Rpt. 20-347, Jet Propulsion Lab., Institute of Technology, Pasadena, Calif., 1958. 

C. A. Detthng, ml 991JANNAF Propulsion Systems Ha ard Subcommittee Meeting, CPIA Pubhcation 562, Sandia National Labs, Albuquerque,... 

A. A.]ah LS,z,Mctmties in Electrothermal Gun Propulsion, CPIA Publication 528, Vol 1, CPIA, Johns Hopkins University, Laurel,Md., 1989,p. 103. 

R. A. McKay,M Study of Selected Parameters in S olid Propellant Processing,]et Propulsion Lab, Pasadena, Calif., Aug. 1986 J. L. Brown and co-workers. Manufacturing Technologyfor SolidPropellantIngredients/Preparation Reclamation, Morton Thiokol, Inc., Brigham City, Utah, Apt. 1985 W. P. Sampson, Eow Cost Continuous Processing of Solid Rocket Propellant, Al-TR-90-008, Astronautics Laboiatoiy/TSTR, Edwards AEB, Oct. 1990. 

J. E. Tormey, "Processing and Manufactuie of Composite Propellants," Proceedings of the AGARD Colloquim, Advances in Tactical Rocket Propulsion, CIRA Pub., Pelham, New York, 1968. 

The Annual Proceedings of the Joiat Army-Navy-Air Force (JANNAF) Propulsion Meetings, the reports of the special committees, and the periodic hterature surveys pubHshed by the Chemical Propulsion Information Agency including the aimual Chemical Propulsion Abstracts are iuvaluable sources of information on all aspects of Hquid and soHd gun and rocket propellants. They maybe classified. 

M. H. Smith, "The Literature of Rocket Propulsion," ia The Eiterature of Chemical Technology, Mdvances in Chemisty, Series No. 74, American Chemical Society, Washington, D.C., 1968, p. 581. 

G. P. Sutton, Rocket Propulsion Elements, 5th ed., John Wiley Sons, Inc., New York, 1986. 

S. S. Peimer, Chemical Rocket Propulsion and Combustion Research, Gordon and Breach Science PubHshers, New York, 1962. 

Journal of Ballistics, Memorials de Poudres, aimual summaries of the Chemical Propulsion Information Agency (classified). 

V. N. Huff and S. Gordon, Fables of Thermodynamics Functions forHnalysis ofHircraft-Propulsion Systems, Tech. No. 2161, National Advisory Committee... 

L. A. Dee, Analysis of Nitrogen Trifluoride, AERPL-TR-76-20 (AD-A022887), Air Eorce Rocket Propulsion Laboratory, Edward Air Eorce Base,... 

R. F. Muraca, J. Neff, and J. S. Whittick, Physical Properties ofEiquid Oyygen D fluoride and Eiquid Diborane—M Critical Review, Report No. NASA-CR-88519, SRI-951581-4, Jet Propulsion Lab., Calif. Inst, of Tech., Pasadena, Stanford Research Inst., Menlo Park, Calif., July 1967. 

C. J. Hoffman, Phosphorus—Fluorine Oxidi rs, PF-150613-1, Part 7, Propulsion Chemistry Part II, Lockheed Aircraft Corp., Missiles and Space Div., Burbank, Calif., 1959. 

Energy Partners, Inc. (West Palm Beach, Florida), acquired fuel ceU technology from TreadweU Corp. (Thomaston, Coimecticut), which suppHed electrochemical equipment to the U.S. Navy. Energy Partners, Inc. are involved in developing PEECs for propulsion appHcations in transportation and submersible vehicles. A 20-kW PEEC stack was designed for demonstration tests. 

From the standpoint of commercialization of fuel ceU technologies, there are two challenges initial cost and reHable life. The initial selling price of the 200-kW PAFC power plant from IFC was about 3500/kW. A competitive price is projected to be about 1500/kW orless for the utiHty and commercial on-site markets. For transportation appHcations, cost is also a critical issue. The fuel ceU must compete with conventional mass-produced propulsion systems. Furthermore, it is not clear if the manufacturing cost per kilowatt of small fuel ceU systems can be lower than the cost of much larger units. The life of a fuel ceU stack must be five years minimum for utiHty appHcations, and reHable, maintenance-free operation must be achieved over this time period. The projection for the PAFC stack is a five year life, but reHable operation has yet to be demonstrated for this period. 

H. Shaw, C. D. Kalfadehs, and C. E. Jahnig, Evaluation of Methods to Produce Aviation Turbine Fuels From Synthetic Crude Oils-Phase I, Technical Report AFAPL-TR-75-10, Vol. 1, Air Force Aero Propulsion Laboratory, Wright-Patterson Air Force Base, Dayton, Ohio, Mar. 1975. 

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