Solid-fueled rockets

J. Taylor and Sillitto found that ammonium nitrate mixed with 3% of potassium chromate or bichromate undergoes spontaneous decomposition ( burning ) on being heated to about 400°C. J. Taylor et al. [5, 27] suggest utilizing mixtures made from ammonium nitrate and potassium chromate as the main component of rocket solid fuels. This is described in more detail in Vol. III. 

Hydroxyl-terminated polydiene resins gelled by the reaction with orthosilicate esters have increased thermal stability. These polymeric gels, like silicone rubbers, exhibit outstanding electrical properties. The polymeric gels crosslinked at ambient temperature are castable as self-curing liquids. For example, they are used as binders for rocket solid fuels, in coatings for pipes, tanks, etc. They can be mixed with rubbers. 

The design of propellants for solid fuel rockets differs considerably from that for ordnance, because of the lower operating pressures, usually below 15 MPa. To understand the principles involved it is first necessary to give a brief account of rocket propulsion. In this account considerations will be restricted to motors based on solid propellants. Motors based on liquid fuels, such as petroleum fractions and liquid oxygen, depend on combustion processes of non-explosive type. 

A list of missiles using solid fuel rockets is quoted from Daboo in Table 19.3. 

Table 19.3 Missiles with Solid-fuel Rocket Propulsion... 

Corner, J., Theory of the Interior Ballistics of Guns. Chapman Hall, London, 1950. Daboo, J. E., Solid-fuel Rocket Propulsion. Temple Press, London, 1962. 

Not only must space MS be compact, low power, and autonomously operated, but they must survive launch by rocket. The trend over the past few decades has been toward solid-fueled rockets or boosters that have a much rougher ride than liquid-fueled rockets. Over-zealous specifications often require that space MS survive 15 g of random shake acceleration, which is about like lifting the instrument 10 cm and dropping it on the floor repeatedly. All those shims in a magnetic sector MS must be capable of being realigned in space, perhaps with stepper motors, which is what ESA had to fly in its 2011 comet mission [19]. Likewise, carbon foil technology took an additional 10 years to fly after it had been developed in the laboratory, primarily to ensure that it survived launch. 

However, it must be noted that Eq. (1.62) is applicable for ramjet propulsion, as in ducted rockets and solid-fuel ramjets, because in these cases air enters through the inlet and a pressure difference between the inlet and the exit is set up. The mass flow rate from the inlet m plays a significant role in the generation of thmst in the case of ramjet propulsion. 

Hybrid rockets are intermediate between solid rockets and hquid rockets in terms of the nature of the combination of solid fuel and hquid oxidizer. Since the fuel and oxidizer components of a Hquid rocket are physically separated, two mechanical systems are needed to feed these components into the combustion chamber. On the other hand, a hybrid rocket uses a polymeric inert material as a fuel and a Hquid oxidizer, and so only one mechanical system is needed to feed this Hquid oxidizer into the combusHon chamber. 

Kubota, N., and Kuwahara, T., Energetic Solid Fuels for Ducted Rockets (1), Propellants, Explosives, Pyrotechnics, Vol. 16, pp. 51-54, 1991. 

Uses. To implode fissionable material in nuclear devices to achieve critical mass as a component of plastic-bonded explosives and solid fuel rocket propellants and as burster charges in military munitions. 

The "newest" oxidizer to appear in pyrotechnics, ammonium perchlorate has found considerable use in modern solid-fuel rocket propellants and in the fireworks industry. The space shuttle alone uses approximately two million pounds of solid fuel per launch the mixture is 70% ammonium perchlorate, 16% aluminum metal, and 14% organic polymer. 

Danilin, M. Yu., Local Stratospheric Effects of Solid-Fueled Rocket Emissions, Ann. Geophys., 11, 828-836(1993). 

V.N. Sokol skii, "Russian Solid-Fuel Rockets , CFSTI, Springfield, Va (1967) 236pp... 

Pentaerythrital Tetranitrate (PETN) white, crystalline compound used as a detonating agent in blasting caps and detonating fuse CHEMICAL PROPULSION SYSTEMS PROPULSION SYSTEMS AND GAS GENERATORS Complete solid-fueled rocket motors and gas... 

Hybrid Rocket Propellants. A special proplnt combination of unlike materials, particularly of unlike physical characteristics. Typical hybrid proplnt combinations are a solid fuel (or oxidizer) in combination with a liquid oxidizer (or fuel) in tjiat order. Sometimes a grain of solid fuel is encased in the combustion chamber of a rocket engine and burned in combination with liq oxygen. Similarly, a liq fuel may be injected into a combustion chamber in contact with a solid oxidizer. Another example is the use of concentrated hydrogen peroxide and a hydrocarbon fuel. In this case, the hydrogen peroxide is converted by decompn into a hot gas contg oxygen. The fuel is injected downstream of the first reaction, mixed with the hot oxidizer-rich gas, and burns (Ref 1)... 

Manufacturing Methods for the Production of Infiltrated Tungsten Composite Rocket Nozzle Inserts , AMFL-TR-66-316 (1966) (AD 803450) 5) O. Svejka J. Kozeca, Solid Fuels for Jet, Aircraft and Ship Models , CzechP 123107... 

Boron has been studied as a possible fuel for solid fuel ramjets (10,11). Fine particle sized boron, where the average particle size is 0.3 Lm, has been studied for use as a gas-generating agent for solid fuel ram rockets (12). 

Inertial Confinement. In the inertial approach, the fuel is heated as it is compressed to a very high density, estimated at about I(KK) times that or the normal density of the solid fuel. An intense energy source is focused onto Ihe outer surface of a specially formed spherical pellet. This produces ablation on the outer surface somewhat similar lo the ablation of a rocket as it is exposed to extremely high temperatures. The energy also causes an implosion (an inward bursting) of the deuterium-tritium fuel mixture in the inneT portion of Ihe pellet. The compression process heats the fuel to ignition temperature and also contributes to the quantity of fuel that can be burned. Inasmuch as the compressed fuel is restrained by its own inertia, the fuel hums before it can fly apart. This is a time span of a billionth of a second or less. ... 

Nekrassoff, Contract NOrd 10260(1954), Washington, DC, p22 13)Anon, Exterior Ballistics , USMilAcad,West Point,NY(1949)(Pamphlet) 14)R.N.Wimpress, Interior Ballistics of Solid Fuel Rockets ,McGraw-Hill,NY(1950) 15)J. Comer, Theory of Internal Ballistics of Guns ,... 

PATR 1637(1947XBurning and other characteristics of stick rocket proplnts) 6)S.S.Penner, JApplPhys 19, 392-8(1948) CA 42, 6512(1948)(Effect of radiation on rate of burning of solid fuel rocket proplnts) 7)L.H.Eriksen, Investigation of Asphalt-Perchlorate and Resin-Perchlorate Rocket Propellants , PATR 1676(1948) 8)S.S.Penner, JApplPhys 19, 511-13(1948) CA 42, 8475(1948) (The theory that burning rates of rocket proplnts increase slightly with an increase in radiation path length was verified experimentally for two double-base rocket proplnts) 9)W.G.Thummel,... 

Wimpress, "Internal Ballistics of Solid-Fuel Rockets , McGraw-Hill, NY(1950), 16-28 12)B.L. 

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