s these functions and examine their purpose. The first such device is the thrust chamber. The thrust chamber contains an injector, a combustion chamber and a nozzle. The thrust chamber is the place where the propellants are injected, atomized, then mixed and finally burned to form reaction products in the form of gas. Next, the products are accelerated and ejected at extremely high velocities to create thrust. The injector is a series of pipes that allow the liquid propellant to move into the combustion chamber chamber to be made into thrust while atomizing and mixing them. The exhaust nozzle is the last step in the releasing of thrust. It allows the hot gas to expand and then accelerates them to supersonic velocities. On some vehicles, the nozzle acts as a steering mechanism by placing it on an electronic axis for which it can be turned by an automated steering wheel. There are two major types of feed systems used by LPRs; one uses pumps to move propellants to combustion chambers; the other, uses high pressure to expel propellants from their tanks. On most space vehicles the engines are mounted in pairs at the perimeter of the craft. Normally to opposite facing thrust chambers are controlled automatedly to turn the ship. Generally, a minimum of 12 thrust chambers is required for turning. Solid Propellant Rockets Solid Propellant Rockets (SPRs) contains a huge number of types of engines. The propellant that is to be burned is held in the combustion chamber. The propellant charge (grain) contains chemical elements for complete burning. When it is ignited, it burns on all its exposed sides. If the design of the grain is changed, then less can be exposed; the less exposed, the less fuel burned. The average burning rate is around 1.8 cc per second. The rate normally depends on the propellant ingredients. The more chamber pressure, the more propellant burnt. The wa...
