A rocket engine is a jet engine which works on the principle of action and reaction for moving a vehicle forward/ or upward. It is used on missiles or on spaceships as a means of thrust and propulsion to drive them at an extremely high speed. Since it does not need intake of air, it is capable to perform well in outer space, being able to propel a spacecraft.
The modern and efficient rocket engine was developed by Werner von Braun during World War II. It constituted a revolutionary design and means to drive forward a vehicle as it does not transmit mechanical movement through crankshaft, gears and axle as is the case with an internal combustion engine in a car. The best example of its efficiency and performance was the Saturn V’s 3-stage rocket, which propelled and boosted Apollo 11 out of the Earth’s gravitational field on July 16, 1969.
Essential Parts
A rocket engine consists of a combustion chamber, an injection system, a propellant control valves, an exhaust nozzle (De Laval type), and the propellant (fuel), and the oxidizer. The propellant gases are generated in the combustion chamber at pressures which depend on the chemical characteristics of the propellants, their rate of consumption, and the cross-sectional area of the nozzle throat. The propellants utilized in a rocket motor can be either solid or liquid. Solid propellants is used in rocket which operates for a brief period, up to 50 seconds.
Principle and function
The gases of the propellants ignition are ejected into the atmosphere, or into space, through the nozzle with supersonic velocity. The function of the nozzle is to convert the pressure of the propellant gases into kinetic energy. The reaction to the discharge of the hot gases is the thrust in the opposite direction, imparting the vehicle, on which it is attached, a powerful forward movement.
Below, another diagram of a rocket engine propulsion system, with its different elements.
