Solid ramjet

Pressure Atomization Plain- Orifice 25-250 Diesel engines, Jet engine afterburners, Ramjets Simple, Rugged, Cheap Narrow spray angle, Solid spray cone... 

Recirculation of combustion products can be obtained by several means (1) by inserting solid obstacles in the stream, as in ramjet technology (bluff-body stabilization) (2) by directing part of the flow or one of the flow constituents, usually air, opposed or normal to the main stream, as in gas turbine combustion chambers (aerodynamic stabilization), or (3) by using a step in the wall enclosure (step stabilization), as in the so-called dump combustors. These modes of stabilization are depicted in Fig. 4.52. Complete reviews of flame stabilization of premixed turbulent gases appear in Refs. [66, 67],... 

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. 

Solid Rockets, Liquid Ramjets, and Ducted Rockets... 

Ducted rockets are intermediate between solid rockets and liquid ramjets in their propulsion characteristics. The propulsive force of soHd rockets is generated by the combustion of propellants composed of oxidizer and fuel components. Thus, no additional fuels or oxidizers need to be introduced from the atmosphere into the rocket motor. The momentum change of the exhaust gas from the nozzle attached to the aft-end of the combustion chamber is converted into the thrust for propulsion. On the other hand, the propulsive force of Hquid ramjets is generated by the combustion of a liquid hydrocarbon fuel with air introduced from the atmo-sphere.Ii] jjjg incoming air is compressed by a shock wave formed at the air-intake attached to the front end of the combustor. The air taken in from the atmosphere serves only as the oxidizer for the ramjets. The thrust is created by the momentum difference between the exhaust gas from the combustor and the air taken in from the atmosphere. 

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). 

Limitations on temperatures of solid materials often cause the methods of stabilization by solid elements, discussed so far, to be impractical. In most applications of stabilization by solid elements the flame is attached in the wake behind the element, so that the solid is not fully exposed to the flame temperature. Representative examples are bluff-body flame stabilizers, such as the stabilizing rods or plates placed normal to the flow in ramjets and afterburners, which were mentioned in Sections 5.1.1 and 10.3.5. A distinctive feature of bluff-body flame stabilization is the presence of a recirculation zone behind the body. Unlike the alternate vortices shed from bluff bodies in cold flow over the Reynolds-number range of practical interest, a well-defined vortex, steady in the mean, is observed to exist just downstream from the stabilizer when combustion occurs. This is a toroidal vortex for an axisymmetric stabilizer or a pair of identical counterrotating line vortices for rodlike stabilizers. The reason for the drastic change in the... 

SA-4 Gancf USSR L = 880 100,000 Ramjet and solid boosters radio command 70 135 kg ADM... 

Figure 14.8 Structure of a solid fuel ramjet (SFRj).

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